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Coronary Heart Disease
Overview
Over time, these fatty deposits can grow large enough to restrict blood flow to the heart muscle. The diminished blood flow can cause chest pain, or angina. When the blood flow in one or more coronary arteries is completely cut off, the result is a heart attack, or injury to the heart muscle. The widespread use of cholesterol-lowering drugs has helped reduce the number of heart attacks. And for those who do have them, clotbusters and other medications, improved technologies, and physician awareness of such lifesaving measures as providing a beta blocker to heart attack patients as they leave the hospital have helped more people survive heart attacks and go on to live many more years. CausesLike all arteries, the coronary arteries are muscular tubes with a smooth lining, allowing blood to flow freely. Yet atherosclerosis begins early in life. Even before the teen years, the blood vessel walls begin to show streaks of fat and cholesterol. As you get older, this fatty matter builds up, slightly injuring the blood vessel walls. The cells inside the walls react by releasing chemicals that make the walls stickier. Other substances floating through your bloodstream, such as platelets (disk-shaped particles that aid clotting), inflammatory cells, proteins, and calcium, adhere to the walls. The fat and other substances combine to form larger deposits, called plaques. Over time, these plaques can build up, narrowing the channel through which blood flows. If the narrowing is severe, the heart muscle becomes oxygen-starved, a condition called ischemia. As the size of a blockage increases, sometimes a narrowed artery develops "collateral circulation," growing small, capillary-like branches that reroute blood around the narrowed area. During increased exertion, however, these "collaterals" might be unable to meet the heart muscle's demand for oxygen. The fatty plaques may develop a hard, fibrous "cap" over the soft, mushy contents. If the hard surface cracks or tears, the fatty insides will leak or gush out. Clot-forming cells called platelets come to the area and create a blood clot around the material ejected from the plaque. The clot might subsequently break apart on its own, restoring blood flow. More commonly, however, it lodges in the vessel, narrowing it further or blocking it entirely. A blood clot that completely occludes the artery is called a coronary thrombus or coronary occlusion, and it will cause one of three types of problems, all of which are life-threatening emergencies: Unstable angina: This may be a new symptom or a change from stable angina. The angina may occur more frequently, occur more easily at rest, feel more severe, or last longer. Although this angina can often be relieved with oral medications, it is unstable and may progress to a heart attack. Usually more intense medical treatment or a procedure is required. Unstable angina is an acute coronary syndrome and should be treated as a medical emergency. Non-ST segment elevation myocardial infarction (NSTEMI): This heart attack, or MI, does not cause changes on an electrocardiogram (ECG). However, chemical markers in the blood indicate that damage has occurred to the heart muscle. In NSTEMI, the blockage may be partial or temporary, and so the extent of the damage relatively minimal. ST segment elevation myocardial infarction (STEMI): This heart attack, or MI, is caused by a prolonged period of blocked blood supply. It affects a large area of the heart muscle, and so causes changes on the ECG as well as in blood levels of key chemical markers. Risk Factors Age. The older you get, the more likely you are to develop heart disease. Approximately 85 percent of people who die of coronary artery disease are older than 65. Gender. Men have a greater risk than women of having a heart attack, particularly at a younger age, but more women than men die from them. The rate of male CAD has remained flat while the incidence of female CAD has risen dramatically. Menopause. Prior to menopause, the hormone estrogen helps protect against CAD. Afterward, changes in the walls of the blood vessels make it more likely for plaque and blood clots to form. Changes occur in the level of lipids (fats) in the blood. There is an increase in fibrinogen (a substance in the blood that helps the blood to clot). Increased levels of blood fibrinogen are related to heart disease and stroke. After menopause, a woman's risk increases until at age 70, women and men have equal chances of dying from heart disease. Post-menopausal women have a higher rate of complications and death than men after bypass surgery and angioplasty. But this may be related in part to the fact that women's symptoms of coronary artery disease are not as typical, so they may not get treatment until their disease is more advanced. This section includes a note about hormone replacement therapy (HRT) and the risk of heart disease. Family history. If a first-degree relative—either of your parents, your brothers or sisters, or your children—has had heart disease, your own risk of CAD is higher. If that relative is a male younger than 55 or a female younger than 65, the risk is much higher. A note about hormone replacement therapy and heart disease risk More recent studies of women, such as the Heart and Estrogen/progestin Replacement Study (HERS) and the Women's Health Initiative (WHI) concluded that overall health risks exceed the benefits provided by HRT. Women who participated in the WHI showed an increased risk for breast cancer, CAD (including nonfatal heart attacks), stroke, blood clots, and gall bladder disease. Based on the results of these studies, women who already have heart disease should not take HRT. There are other risks and benefits from HRT. It is important to discuss the risks and benefits of HRT with your own doctor before making a decision. For more information, see http://www.nhlbi.nih.gov/health/women/pht_facts.htm. Prevention
The single most essential element in primary prevention centers on a set of measures collectively termed therapeutic lifestyle changes (aptly termed TLC in the latest treatment guidelines from the government-sponsored National Cholesterol Education Program). Heeding all the TLC recommendations all the time is not easy. But research shows that making even the smallest lifestyle changes can reduce the risk of coronary artery disease, heart attack, stroke, and other serious cardiovascular conditions. Stop smoking. Smoking is the biggest risk factor for sudden cardiac death. Smoking even one to two cigarettes a day greatly increases the risk of heart attack, stroke, and other cardiovascular conditions or events. Cigarette, pipe, and cigar smokers all have more than double the risk of a heart attack than nonsmokers. Goal: Stop smoking. Lower your blood level of total cholesterol, LDL cholesterol, and triglycerides. Fatty substances in your blood such as LDL cholesterol and triglycerides cause fatty deposits to build up in your arteries. The deposits can reduce or block the flow of blood and oxygen to your heart. If your total cholesterol levels are above 240 milligrams per deciliter (mg/dL), your risk of CAD is high, but your risk begins rising when your total cholesterol is above 200 mg/dL. Without a family history of cardiovascular disease or high cholesterol, women should have a cholesterol profile done annually starting at age 40, men at age 30. If there is a family history of cardiovascular disease or hyperlipidemias, you should have your lipid profile checked at age 20 or even in childhood. Goal: LDL cholesterol should be less than 70 mg/dl for those with heart or blood vessel disease and other patients at very high risk of cardiovascular disease, such as those with metabolic syndrome. LDL cholesterol should be less than 100 mg/dl for those who have a high risk of cardiovascular disease, such as some patients with diabetes or those who have multiple heart disease risk factors. For all others, LDL cholesterol should be less than 130 mg/dl. Triglycerides are also linked to heart and blood vessel disease. Triglyceride levels should be less than 150 mg/dl. Raise your level of HDL or "good" cholesterol. HDL cholesterol carries LDL, or "bad," cholesterol away from the arteries back to the liver, which removes it from the bloodstream. High levels of HDL apparently protect against cardiovascular disease. Goal: The higher the HDL, the better. An HDL level below 40 mg/dL is considered a risk factor. Bring down high blood pressure. Blood pressure is an indication of the force applied in your arteries as your heart beats. High blood pressure (or hypertension) increases the workload of the heart and kidneys, increasing your risk of a heart attack, heart failure, stroke, and kidney disease. It is the biggest risk factor for stroke. Goal: The latest standards say that normal blood pressure is below 120/80 and that high blood pressure is 140/90 (blood pressure of 120-139/80-89 is considered pre-hypertension). Diet, exercise, bringing your weight to normal levels, and, if needed, medications can control high blood pressure. Since alcohol can increase your blood pressure, it's best to limit alcohol to the recommended equivalent of one glass of wine daily. Control diabetes. Diabetes occurs when your body can't produce insulin, the hormone that breaks down digested sugars, or utilize the insulin it does produce. That allows blood sugar to escalate to a harmful level. Controlling diabetes is essential for reducing your risk of CAD, because diabetes is a major independent risk factor for cardiovascular disease and raises the level of LDL and triglycerides, lowers HDL, and elevates blood pressure. In fact, in terms of heart attack risk, someone with diabetes, whether male or female, is put in the same category as someone with proven heart disease and is a candidate for secondary prevention. Diabetes increases the risk of heart disease in women more than in men. Goal: Keep the condition under control with diet, exercise, faithful monitoring of blood glucose, and other measures recommended by the doctor monitoring you. The hemoglobin A1c test, often called the "diabetic report," provides an average blood sugar level over a 2 to 3 period. It should be less than 7 percent if you have diabetes and less than 6 percent if you do not. Maintain a healthy body weight. The more you weigh, the harder your heart has to work. Overweight individuals are much more subject to cardiovascular disease than are their trim counterparts. Excess weight raises blood cholesterol, triglycerides, and blood pressure, and lowers HDL cholesterol. It also increases your risk of diabetes. How excess weight is distributed is important. Fat concentrated in your midsection puts you at greater cardiovascular risk than extra pounds in the arms and legs. To identify the way your fat is distributed, measure your waist. Waist measurements for women should be less than 35 inches. Men should aim for a waist less than 40 inches. Your body mass index (BMI), a figure that combines height and weight, is recommended by the National Institutes of Health to check whether you are overweight or obese. The BMI is calculated by dividing your weight in kilograms by your height in meters, squared. (Divide pounds by 2.2 to get your weight in kilograms and multiply your height in inches by 0.0254 to get your height in meters.) You can do the calculation yourself or go to our BMI calculator that will do it for you. A normal BMI ranges from 18.5 to 24.9. Overweight is defined as higher than 25 and obesity as higher than 30. Goal: If your BMI puts you in the obese or overweight categories, work to drop down to the normal range. Move your body. Your heart, like any other muscle, needs a workout to stay strong. Activity and exercise, coupled with a healthy body weight, interact with many other risk factors and help you prevent heart disease. Goal: Moderate exercise 30 minutes a day on most days of the week. More vigorous activities are associated with more benefits. But be sure to consult your doctor before starting any exercise program. To achieve cardiovascular benefits, exercise should be aerobic, involving the large muscle groups. Aerobic activities include brisk walking, cycling, swimming, jumping rope, and jogging. If walking is your exercise of choice, use a pedometer and aim at least 10,000 steps a day. Follow a heart-healthy diet. The old saying, "You are what you eat," is true especially when you want to prevent cardiovascular disease. Four cardiac risk factors result from dietary mismanagement: high blood pressure, high blood cholesterol, diabetes, and obesity. Goals: Eat foods low in sodium, cholesterol, and saturated fats, and shun trans fats—partially hydrogenated fats used in butter substitutes and processed foods. Stay away from foods containing refined sugar such as pies, cakes, cookies, and ice cream. Try to eat foods containing omega-3 fatty acids, good fats found in tuna, salmon, flaxseed, almonds, and walnuts. Mono-unsaturated fats, found in olive and peanut oils, are also good for you. According to the latest 2005 U.S. dietary recommendations, you should strive every day to eat at least nine plant-based foods, which are fruit, vegetables, nuts, and whole grains. Reduce stress. Several researchers have noted a relationship between cardiovascular disease risk and stressful responses, including free-floating hostility, to everyday events, intimate relationships, and particularly to their socioeconomic status. Goal: Manage stress by practicing relaxation techniques, learning how to manage your time, and setting realistic goals. Limit alcohol consumption. Heavy drinking can raise your blood pressure, increase your risk of heart failure and stroke, as well as cause heart palpitations. It is also linked to obesity and cancer. Goal: Moderation is the key. If you already drink, it's best to limit alcohol to the recommended equivalent of one glass of wine daily. If you don't drink the American Heart Association cautions you not to start because it's impossible to predict whether you might develop a drinking problem. Know your risk factors. If you have a family history of cardiovascular disease or high cholesterol, it is important for you to try to lower your risk on other fronts. It is also vital have your cholesterol levels tested yearly and see your health care provider yearly for a checkup. Symptoms
Chest pain
Angina is the most common symptom. It is an uncomfortable feeling that usually is felt in the chest just beneath the breastbone, but other possible sites include the left shoulder, arms, neck, throat, jaw, or back. Those who have experienced angina typically describe as a heaviness or pressure ("an elephant on my chest"), aching, burning, fullness, squeezing, and pain. It can be mistaken for indigestion. Angina episodes usually stop in a minute or so. But if one lasts more than about 15 minutes, you should seek emergency treatment. For more information, see our additional page on the three types of angina. Symptoms in women Women seem to be protected against heart disease in their childbearing years. Thus, on average they tend to develop coronary artery disease about 10 years later than men, have heart attacks about 20 years later, and often have different symptoms. A heart attack may be felt as chest pain, or it may feel like a general discomfort in the chest or other parts of the body, shortness of breath, or nausea. Not all physicians are familiar with these male-female differences and are less likely to diagnose a heart attack in a woman than in a man. Making the problem worse is the fact that women tend to associate heart attacks with men and are less likely to recognize the symptoms in themselves and seek treatment. IF YOU HAVE POSSIBLE CAD SYMPTOMS: 1. Learn to recognize your symptoms and the situations that cause them. Call your doctor if you have new symptoms or if they increase in frequency or intensity. 2. If angina occurs, stop what you are doing and rest. If your doctor has prescribed nitroglycerin to relieve the symptoms, take one tablet and let it dissolve under your tongue (if using the spray form, spray it under your tongue). Wait five minutes. If the symptoms persist, take another dose. If you still have angina after resting and taking two doses of nitroglycerin, or 10 minutes, call for emergency help or have someone take you to the local emergency room. 3. If you think you may be having a heart attack, call 911 for emergency help. Do not delay-quick treatment is critical to minimize the damage to your heart. To help break up a possible clot, emergency personnel may tell you to chew an aspirin, if there is not a medical reason for you to refrain from doing so. Types of angina
Stable angina is brought on by an imbalance between the heart's need for oxygen-rich blood and the amount available. It is "stable" in the sense that the same activities bring it on; it feels the same way each time; and it is relieved by rest and/or oral medications. Stable angina is a warning of heart disease and should be evaluated by a doctor. If the pattern of angina changes, it may progress to unstable angina. Unstable angina may be a new symptom or a change from stable angina. The angina may occur more frequently, occur more easily at rest, feel more severe, or last longer. Although this angina can often be relieved with oral medications, it is unstable and may progress to a heart attack. Usually more intense medical treatment or a procedure is required. Unstable angina is an acute coronary syndrome and should be treated as an emergency. Variant angina (also called Prinzmetal's angina or coronary spasm) occurs when a coronary artery goes into spasm, disrupting blood flow to the heart muscle (ischemia). It can occur in people without significant coronary artery disease. However, two thirds of people with variant angina have severe disease in at least one vessel, and the spasm occurs at the site of blockage. This type of angina is uncommon and almost always occurs when a person is at rest, especially while asleep. You are at increased risk for coronary spasm if you: have underlying coronary artery disease, smoke, or use stimulants or illicit drugs (such as cocaine). If a coronary artery spasm is severe and occurs for a long period of time, a heart attack can occur. Tests
Electrocardiographic tests
In our section on electrocardiograph tests you will find:
Ambulatory monitors
Your doctor uses ambulatory monitors to:
Holter monitor (also called ambulatory EKG): This device is a portable EKG recorder that you wear during your normal daily activities, including sleeping. It can be worn for one to three days. Small sticky electrode patches are placed on the skin of your chest. Wires are attached from the electrodes to a box about the size of a portable tape player that is worn on a belt or shoulder strap. The monitor continuously records and stores the heart's electrical impulses. While wearing the monitor, you will be asked to keep a diary of your activities and symptoms, such as fluttering feelings in your chest (palpitations), rapid heartbeats, and episodes of dizziness or faintness. Keeping track of the activities you were doing when your symptoms occurred is important, so your doctor can see what kinds of events are bringing on your symptoms. When you complete your Holter monitor test, a technician will play the tape on a computer that analyzes the recording and detects the appearance of any rhythmic abnormalities. The technician prepares a report with a printout of any abnormal heart rhythms for the doctor to study. Loop recorder (event recorder): This device is worn 24 hours a day except when showering or bathing. This monitor is worn for about a month and is used for patients who have less frequent arrhythmia episodes and symptoms. The technologist attaches small electrodes to your chest and attaches wires from the electrodes to a box about the size of a portable tape player. Like the Holter, the loop recorder can hook to your belt or shoulder strap. Whenever you feel symptoms, you depress a button. The monitor stores its recording of the event for the 60 seconds before your pushing the button and up to 40 seconds after the event is over. The loop recorder can store up to three events. The recording of the rhythm can be transmitted later over the phone lines. The technician will give the recordings to your doctor for review. If the reading indicates an emergency, the technician will instruct you to go to an emergency room. Transtelephonic transmitters: This device is not worn continuously. It is used only during the period when data picked up by the device are transmitted over the phone for evaluation by a physician. In the past, this type of transmitter was used for monitoring pacemaker function. However, now it also is used for patients with arrhythmias. It is particularly useful for evaluating symptoms that occur rarely, so usually are not evident during an office visit. When you develop symptoms, a strip of your current heart rhythm can be transmitted to your doctor's office over the phone using a monitor with two bracelets or by placing the monitor against your chest wall.
Electrocardiogram
Your doctor uses the test to:
What to expect: During a resting EKG, a technician will attach 10 electrodes with adhesive pads to the skin of your chest, arms, and legs. Men may have chest hair shaved to allow a better connection. You will lie flat during the test. It takes about 10 minutes to attach the electrodes and complete the test; the actual recording takes a few seconds. Your EKG patterns will be kept on file for comparison with future ECG recordings.
Exercise stress test
Your doctor uses the test to:
To prepare:
What to expect: Small, sticky electrode patches are attached to 10 areas of your chest. Men may expect to have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor that will chart your heart's electrical activity during the test. You will begin to exercise by walking on a treadmill or pedaling a stationary cycle. The degree of difficulty will gradually increase until you are exercising very hard. At regular intervals, the lab personnel will ask how you feel. Be sure to tell them if you feel chest, arm, or jaw pain; shortness of breath; dizziness; or any other unusual symptoms. It is normal for your heart rate, blood pressure, and breathing rate to increase during the test, as well as the amount you perspire. In addition, the lab personnel will watch for any symptoms or changes on the EKG monitor suggesting the test should be stopped. After the test you will walk or pedal slowly for a couple of minutes to cool down. Your heart rate, blood pressure, and EKG will continue to be monitored until readings begin returning to normal. The appointment lasts about 60 minutes; the actual exercise time is usually between seven and 12 minutes.
Head upright tilt test
Your doctor uses the test to:
To prepare:
What to expect: Before the test you will be asked to lie on a motorized bed that can be tilted to different degrees, as described above. Your feet will rest against a metal plate for support when you are tilted upright. The nurse will start an intravenous (IV) line in your arm to give you medications and fluids during the procedure, and, if necessary, to treat your symptoms and/or blood pressure and heart rate changes. The nurse will connect you to several monitors (for monitoring your heart's electrical activity, your blood pressure, and sometimes respiration and the level of oxygen in your blood). For your safety, soft straps will be secured across your body before the test begins. While you lie quietly with your legs still, the bed will be tilted at different angles. Although you may feel no symptoms at all, you should be sure to report any feelings of lightheadedness, nausea, or dizziness, any palpitations (fluttering in the chest) or blurred vision. The HUT lasts about one hour and 15 minutes. At the end of the test, the findings may indicate you need the test repeated or that you will need further tests. If a repeat tilt test is performed, it will be given with up to three segments, each with a supine (flat) and a 70-degree portion. Your doctor may give you a medication called Isuprel, which causes your heart to respond as if you were exercising. It may make you feel nervous, jittery, or that your heart is beating faster or stronger. This feeling will go away as the medication wears off.
Metabolic exercise stress test
Your doctor uses the test to:
To prepare:
What to expect: A technician will attach small, sticky electrode patches to 10 areas of your chest. Men may expect to have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. Before you start exercising, the technician will perform a resting EKG, measure your heart rate and take your blood pressure. You also will be asked to breathe through a mouthpiece for a few minutes before the test begins and throughout your test. A clip will be placed on your nose so you breathe only through your mouth. You will begin to exercise by walking on a treadmill or pedaling a stationary cycle. The degree of difficulty will gradually increase until you are exercising very hard. Your blood pressure, heart rate, EKG, and other breathing measurements will be taken throughout the test. At regular intervals, the technician will ask how you feel. Since you will be unable to talk with the mouthpiece in place, they will ask you questions that can be answered by nodding "yes" or shaking "no." Be sure to tell them if you feel chest, arm, or jaw pain; shortness of breath; dizziness; lightheadedness; or any other unusual symptoms. It is normal for your heart rate, blood pressure, and breathing rate to increase during the test, as well as the amount you perspire. You may also have a dry mouth from breathing through the mouthpiece. The lab personnel will watch for any symptoms or changes on the EKG monitor that suggest the test should be stopped. After the test you will walk or pedal slowly for a couple of minutes to cool down. Your heart rate, blood pressure, and EKG will continue to be monitored until the readings begin returning to normal. The appointment will last about one hour and 15 minutes; actual exercise time is usually between five and 12 minutes.
Laboratory
Lab values listed in the following sections are those for the Cleveland Clinic Foundation Laboratory. Abnormal test results do not always indicate disease. You should discuss all blood test results with your doctor. In this section on laboratory tests you will find:
Lipid blood tests
Total cholesterol (TC): Directly linked to risk of heart and blood vessel disease. Cholesterol is a fatty molecule in the blood that is produced by the liver and consumed in animal products. Your body needs cholesterol to maintain the health of your cells. But too much leads to coronary artery disease.
Target values:
Preparation:
High-density lipoprotein (HDL): High blood levels of this fatty molecule, known as the "good" cholesterol, are usually linked to a reduced risk of heart and blood vessel disease. Many researchers believe HDL is "good" because it removes excess cholesterol from the blood.
Target value:
Preparation:
Low-density lipoprotein (LDL): High blood levels of this fatty molecule, known as the "bad cholesterol," are linked to an increased risk of cardiovascular disease, including coronary artery disease. Reducing LDL has become a major treatment target for cholesterol-lowering medications.
Target values:
Preparation:
Triglycerides (TG): High blood levels of triglycerides are associated with heart and blood-vessel disease. The blood level of this type of fat is mostly affected by alcohol and foods such as sugar and fat. Other causes of a high TG level can be obesity and thyroid or liver disease.
Target value:
Preparation:
Blood tests to determine your risk of CAD
Lipoprotein a (Lp[a]): Researchers do not yet know all the functions of Lp(a), but if a patient's level is greater than 30 mg/dl he or she has a greater risk of suffering a heart attack or stroke. An elevated level of Lp(a) also is linked to the development of fatty matter vein grafts after bypass surgery, to coronary artery narrowing after angioplasty, and to the development of blood clots.
Target value:
Preparation:
Apolipoprotein A1 (Apo A1): Apo A1 is the major protein of HDL. Low levels are associated with a diet high in fat and smoking and may indicate the risk of early heart and blood vessel disease.
Target value:
Preparation:
Apolipoprotein B (ApoB): This protein is found in cholesterol particles. Recent research suggests ApoB may be a better overall marker of risk than LDL alone.
Target value:
Preparation:
Homocysteine (Hcy): High levels of homocysteine are associated with an increased risk of cardiovascular disease. Both folic acid and B vitamins naturally break down homocysteine in the blood. While treatment with folic acid and B vitamins have not been shown to clearly reduce the risk of cardiovascular disease, it is recommended that people get enough folic acid and vitamins B-6 and B-12 in their diet. Supplements can be used when one's diet does not provide enough of these nutrients.
Target value:
Preparation
Fibrinogen: This blood protein is necessary for clotting. High levels may be an independent risk factor for cardiovascular disease. Higher blood pressure, excess body weight, elevated blood levels of LDL, diabetes, and advancing age are linked to higher levels of fibrinogen. Alcohol use and exercise are related to lower fibrinogen levels.
Target value:
Preparation:
Ultra Sensitive C-reactive protein (US-CRP, also called high sensitivity CRP): The presence of this protein in the blood indicates a heightened state of inflammation in the body. Inflammation is the body's normal response to physical problems such as fever, injury, and infection. In addition, studies show that elevated CRP correlates with increased risk for heart attack, stroke, peripheral vascular disease, and reclosing of coronary arteries after angioplasty. For now, clinical guidelines do not recommend a routine CRP test for those with no indication of heart disease. For those with elevated US-CRP, low-dose aspirin (100 mg or less) daily may provide protection from cardiac disease. Statin drugs, which lower LDL, also seem to reduce US-CRP levels. Do not begin taking these medications for high US-CRP levels without speaking with your physician.
Target values:
Preparation:
Electrolyte tests
Sodium:
Magnesium:
Potassium:
Enzymes and proteins
Alanine aminotransferase (ALT, SGPT): This enzyme is measured to detect lever damage and hepatitis. Some medications, including statins to lower lipid levels, may elevate the ALT, which needs regular monitoring.
Target value:
Preparation:
Aspartate aminotransferase (AST; also called SGOT): This enzyme is released into the bloodstream following injury or death of cells. Increased AST is seen with liver disease, myocardial infarction, or heart attack and with the use of some medications, such as statins that reduce lipid levels. Like ALT, AST needs regular monitoring.
Target value:
Preparation:
Creatinine (CR): Creatinine becomes elevated with illness, kidney disease, muscle injury, and with the use of some medications.
Target value:
Preparation:
Creatine kinase (CK): This enzyme rises when the heart or skeletal muscles are injured. Strenuous exercise, weightlifting, surgical procedures, and high doses of aspirin and other medications may cause elevated levels.
Target value:
Some laboratories report the CK as percentages with CK-MD as one CK type; for example, CKBB: 0%; CKMB: 0-4%; CKMM: 96-100%
Preparation:
Lactate dehydrogenase (LDH): This enzyme is released in the blood with cell injury. It is often used as a marker to detect a heart attack. It is also elevated with liver and kidney disease, pernicious and megaloblastic anemias, malignancy, progressive muscular dystrophy, and pulmonary emboli.
Target value:
Preparation:
Myoglobin (Mb): This protein is found in certain types of muscles. Elevated myoglobin may indicate muscle injury or inflammation.
Target value:
Preparation:
Troponin T (cTNT): This blood protein is related to the heart muscle's ability to contract. For people experiencing chest pain or discomfort, its level may reveal acute damage to the heart muscle and impending risk of myocardial infarction.
Target value:
Preparation:
Blood tests for those taking anticoagulants
Prothrombin time (PT): PT is a test to determine how fast it takes for your blood to clot. Usually when taking a "blood thinner," such as warfarin (Coumadin), the desired PT is about 1 1/2 times normal. When checking PT, your doctor will receive the results and let you know if you are taking the correct amount of blood thinner medication.
Target value:
Preparation: International normalized ratio (INR): INR is tested for those on anticoagulant medications to prevent stroke, embolism, and heart attack. Target value: Normal level for an adult: 0.9-1.2. Your doctor will determine your therapeutic range. Preparation: This test may be measured any time of the day without fasting.
Nuclear imaging
During the test or "scan," you lie on a table while a special "gamma" camera takes a series of pictures. A computer connected to the camera detects the radiation from the body organ being examined and forms a series of images. These images are interpreted by a nuclear medicine physician who searches for abnormal organ function or disease and then makes a diagnosis. The amount of time nuclear imaging takes depends on the type of test. Most studies take about one hour or more. Some require more than one visit. In our section on nuclear imaging you will find:
Multigated acquisition scan
What to expect: A technician will attach 10 electrodes with adhesive pads to the skin of your chest. Men may have patches of chest hair shaved to allow a better connection. The electrodes are hooked up to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. An intravenous (IV) line will be inserted into a vein in your arm. The technician will perform a resting EKG, measure your resting heart rate, and take your blood pressure. The technician will ask you to lie on the exam table under a camera. A small amount of blood is withdrawn and mixed with a radioactive tracer. The radioactive tracer binds to the red blood cells, and the mixture is reinjected into the IV. The tracer stays in the bloodstream for several hours and does not enter your tissue cells. A large camera, located above the table, is focused on the heart and analyzes the amount of radio-labeled red blood cells pumped out of the heart with each heartbeat. The MUGA scan takes about one to two hours to perform.
Thallium exercise stress test
Your doctor uses a thallium stress test to:
What to expect: Ten small areas of your chest are cleaned, and small sticky electrode patches are attached to these areas. Men may have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. Your blood pressure and EKG recording will be taken before, during, and after exercise. You will walk on a treadmill or pedal a stationary cycle. The degree of difficulty will gradually increase. You will be asked to exercise very hard, until you are exhausted. At regular intervals, the lab personnel will ask how you are feeling. Tell them if you feel chest, arm, or jaw pain or discomfort; shortness of breath; dizziness; lightheadedness; or any other unusual symptoms. It is normal for your heart rate, blood pressure, breathing rate, and perspiration to increase during the test. The lab personnel will watch for any symptoms or changes on the EKG monitor that suggest the test should be stopped. At your maximum level of exercise, a small amount of thallium is injected into a vein. The thallium travels through the bloodstream, reaching the coronary arteries and then the cells of the heart muscle. A camera detects the distribution of thallium in the myocardium. Because the thallium works as a tracer to indicate the areas of the myocardium that blood is reaching, regions that show less thallium have a loss of perfusion, or blood flow. After the test you will walk or pedal slowly for a couple of minutes to cool down. Your heart rate, blood pressure, and EKG will continue to be monitored until the levels begin returning to normal. The appointment lasts about 60 minutes, with the actual exercise time usually taking between seven and 12 minutes.
Positron emisson tomography
A PET helps your doctor:
To prepare:
What to expect: During a PET scan, a technician will attach 10 electrodes with adhesive pads to the skin of your chest. Men may have chest hair shaved to allow a better connection. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. An intravenous (IV) line will be inserted into a vein in your arm. The technician will perform a resting EKG, measure your resting heart rate and take your blood pressure. The technician will ask you to lie on the exam table under a camera. A small amount of rubidium will be injected into the IV. Rubidium is a radioactive tracer that allows the physician to view the blood flow in your heart when you are at rest. It is not a dye. The physician or nurse will administer a medication called dipyridamole into the IV for about four minutes. The medication will cause your heart to react as if you were exercising. It may cause a warm, flushing feeling and, in some cases, a mild headache. At regular intervals, the lab technicians will ask how you are feeling. Tell them if you feel chest, arm, or jaw pain or discomfort; shortness of breath; dizziness; lightheadedness; or any other unusual symptoms. The technicians also will watch for any changes on the EKG monitor that suggest the test should be stopped. After all the medication has entered your bloodstream, a small amount of rubidium will again be injected into the IV. The rubidium allows the physician to view the blood flow to the heart muscle while it is in stress. The IV will be removed from your arm once all the medication has entered your bloodstream. The appointment will take about three to four hours. The first part of the test will take about one hour. The second part will take about two hours, with the usual exercise time taking between seven and 12 minutes.
Sestamibi exercise stress test
Your doctor uses the sestamibi stress test to:
To prepare:
What to expect: A nuclear medicine technologist will inject a small amount of thallium into a vein in your arm or hand. Thallium is a radioactive tracer that allows the physician to assess your heart function. Thallium is not a dye. You will be asked to lie very still under a camera with your arms over your head for about 15 to 20 minutes. The camera will record images that show the physician blood flow to each area of the heart muscle at rest. Next you will go to the stress lab. A stress technician will clean 10 small areas of your chest and place small sticky electrode patches on these areas. Men may expect to have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. The technician will perform a resting EKG, measure your resting heart rate, and take your blood pressure. An intravenous (IV) line will be started in the back of your hand. You will begin to exercise by walking on a treadmill or pedaling a stationary cycle. The degree of difficulty will gradually increase. You will be asked to exercise very hard until you are exhausted. At regular intervals, the lab personnel will ask how you feel. Be sure to tell them if you feel chest, arm, or jaw pain or discomfort; shortness of breath; dizziness; lightheadedness; or any other unusual symptoms. It is normal for your heart rate, blood pressure, breathing rate, and perspiration to increase during the test. The lab personnel will watch for any symptoms or changes on the EKG monitor that suggest the test should be stopped. Your blood pressure and EKG recording will be taken during your test. One minute before you stop exercising, a small amount of sestamibi (a different type of radioactive tracer) will be injected in the IV. Once the sestamibi is administered, the IV will be removed. You will also be asked to drink milk, which enhances the quality of the images. After the test you will walk or pedal slowly for a couple of minutes to cool down. Your heart rate, blood pressure, and EKG will continue to be monitored until the levels begin returning to normal. About 30 minutes after you have finished exercising, you will be asked to again lie very still under the camera with your arms over your head for about 20 minutes. The camera will record images that show your physician how well blood flows through the coronary arteries to each area of the heart muscle during exercise. You may be asked to return the next day or within a week for a third scan. Your physician will tell you if you need to come back after reviewing the results of the second scan. The appointment lasts about three to four hours, with the actual exercise time usually taking between seven and 12 minutes.
Ultrasound tests
In our section on ultrasound testing you will find:
Echocardiogram
Your doctor uses the echo to:
To prepare:
What to expect: Three sticky electrodes will be attached to your chest and wired to an EKG monitor that charts your heart's electrical activity. You will lie on your left side on an exam table. A specialist called a sonographer will place a wand (called a sound-wave transducer) on several areas of your chest. The wand will have a small amount of cool gel on the end to help get clearer pictures. You may be asked to change positions during the exam to take pictures of different areas of your heart. You may be asked to hold your breath at times. You should feel no major discomfort during the test. You may feel coolness from the gel on the transducer and a slight pressure of the transducer on your chest. The echo test takes about 40 minutes.
Dobutamine stress echocardiogram
To prepare:
Your physician may also ask you to stop taking other heart medications on the day of the test. If you have questions about your medications—ask your physician. Do not stop any medication without first talking with your doctor. Since many over-the counter medications contain caffeine (such as diet pills, NoDoz, Excedrin, and Anacin), do not take any over-the-counter medication that contains caffeine for 24 hours before the test. Ask your physician, pharmacist, or nurse if you have questions about other mediations that may contain caffeine. If you have diabetes and take medications to manage your blood sugar, ask your physician how to adjust your medications the day of your test. Do not take your diabetes medication and skip a meal before the test. If you own a glucose monitor, bring it with you to check your blood sugar levels before and after your test. If you think your blood sugar is low, tell the lab personnel immediately. Plan to eat and take your blood sugar medication after your test. You can wear whatever you like. You will need to change into a hospital gown to wear during the procedure. What to expect: Wires from 10 sticky electrodes on your chest will be attached to an EKG monitor to chart your heart's electrical activity during the test. An intravenous (IV) line will be inserted into a vein in your arm so the dobutamine can be delivered directly into your bloodstream. A cardiac sonographer will perform a resting EKG, measure your heart rate and take your blood pressure. You will lie on your left side on an exam table so that a resting echo can be performed. The sonographer will place a wand (called a sound-wave transducer) on several areas of your chest. The wand will have a small amount of cool gel on the end to help get clearer pictures. A physician or nurse will administer the dobutamine medication into the IV while the cardiac sonographer continues to obtain echo images. Your heart rate will rise and you may feel it beating more strongly. It may cause a warm, flushing feeling and, in some cases, a mild headache. At regular intervals, lab personnel will ask how you are feeling and will check your EKG, blood pressure, and heart rate. The procedure is usually well tolerated, but occasionally there are complications. Lab personnel will watch for any symptoms or changes on the EKG monitor that suggest the test should be stopped. The IV will be removed once all of the medication has entered your bloodstream. The dobutamine stress echo takes about 60 minutes. The actual infusion time is usually 15 minutes. You should plan to stay in the waiting room for at least 30 minutes after completing the procedure, or until all the symptoms you have experienced are resolved.
Transesophageal echocardiogram
TEE is often combined with Doppler ultrasound and color Doppler to evaluate blood flow across the heart's valves. TEE is often used when the results from standard echo studies were not sufficient or when your doctor wants a closer look at your heart.
To prepare:
What to expect: An intravenous (IV) line will be inserted into a vein in your arm or hand so medications can be delivered when necessary. You will be connected to several monitors. An EKG monitor will chart your heart's electrical activity during the test; a blood pressure cuff will be placed on your arm to monitor your blood pressure, and an oximeter will monitor the oxygen level of your blood by means of a clip placed on one finger. You will be given a solution to gargle that will numb your throat. Anesthetic will then be sprayed at the back of your throat. Medication will be injected into the IV line to help you relax during the test. You may feel drowsy. You will be asked to lie on your left side on an exam table. A dental suction tip will be placed in your mouth to remove secretions. The doctor will insert a thin, lubricated endoscope into your mouth and down your throat (this part lasts a few seconds and might feel uncomfortable) into the esophagus. The tube does not interfere with your breathing. You may be asked to swallow at certain times to help pass the tube. Once the probe is in position, pictures of the heart are obtained at various angles (you will not feel this part of the test). Because of the sedative, you may not be entirely awake for the test. The TEE takes about 90 minutes.
Exercise stress echo
To prepare:
Since many over-the counter medications contain caffeine (such as diet pills, NoDoz, Excedrin, and Anacin), do not take any over-the-counter medication that contains caffeine for 24 hours before the test. Ask your physician, pharmacist, or nurse if you have questions about other mediations that may contain caffeine. What to expect: An EKG monitor will be hooked to your chest through sticky electrodes. A resting EKG will be performed and your resting blood pressure taken. You then will be asked to lie on your left side on an exam table so that a resting echo can be performed. The sonographer will place a wand (called a sound-wave transducer) on several areas of your chest. The wand will have a small amount of cool gel on the end to help get clearer pictures. Next, you will be asked to exercise on a treadmill or stationary bicycle at a gradually increasing rate until the point of exhaustion. The lab personnel will watch for changes on the EKG monitor that suggest the test should be stopped. When you cannot exercise any longer, you will get off the treadmill, quickly return to the exam table and lie on your left side for another echocardiogram. It is normal to feel a little unsteady when getting off the treadmill and onto the exam table for the echo as you stop exercising suddenly. If you were exercising on a bike, the sonographer may perform the echo test while you are still pedaling. You may be asked to quickly return to the exam table for another echocardiogram after exercising. Your heart rate, blood pressure, and EKG will continue to be monitored after exercise until the levels begin returning to normal. The appointment takes about 60 minutes. Actual exercise time is usually between seven and 12 minutes.
Radiographic
In this section on radiographic testing you will find:
Calcium-score screening heart scan
How to prepare: Prior to the test, a blood lipid analysis by a specialized laboratory is recommended. This test can be obtained on the day of your exam and requires you to fast for 12 hours before the exam. You may take your medications as usual with sips of water. CT scanners use X-rays. Tell your technologist and your doctor if you are:
What to expect: The technologist will clean three small areas of your chest and place small, sticky electrode patches on these areas. Men may expect to have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. During the scan, you will feel the table move inside a donut-shaped scanner. The high-speed CT scan captures multiple images, synchronized with your heartbeat. A sophisticated computer program, guided by the cardiovascular radiologist, then analyzes the images for presence of calcification within the coronary arteries. The calcium-score screening heart scan takes only a few minutes. After the procedure: You may continue all normal activities and eat as usual after the test.
Cardiac computed tomography
Your doctor uses the cardiac CT to evaluate:
How to prepare:
What to expect: You will change into a hospital gown. A nurse will insert an IV line into a vein in your arm to administer contrast dye during your procedure. You will lie on a special scanning table. The technologist will clean three small areas of your chest and place small, sticky electrode patches on these areas. Men may have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. You will be asked to raise your arms over your head for the duration of the exam. During the scan, you will feel the table move inside a donut-shaped scanner. You will receive a contrast agent through your IV to help produce the images. It is common to feel a warm sensation as the dye circulates through your body. Once the technologist is sure that all the information is collected, the IV will be removed. The CT scan takes about 15 minutes. After the procedure: You may continue all normal activities and eat as usual after the test. Your physician will discuss the results of your test with you. A note about CT and risk: Occasionally, patients experience an adverse reaction to the contrast agent. Some patients develop itching or a rash following the injection. These symptoms are usually self-limiting and resolve without further treatment. Antihistamines can be administered if needed for symptomatic relief. Rarely, a more serious allergic reaction, called an anaphylactic reaction, occurs that may result in breathing difficulty. This reaction is potentially life-threatening and would require medications and treatment to reverse the symptoms. CT scanners use X-rays. For your safety, the amount of radiation exposure is kept to a minimum. Because X-rays can harm a developing fetus, however, this procedure is not recommended if you are pregnant.
Chest X-ray
Your doctor uses this procedure to:
To prepare: No special preparation is necessary. But tell the technician if you may be pregnant. What to expect: An X-ray can be performed in the hospital at the bedside or in the radiology department. Two views will be taken: You will be asked to stand very still with your chest against the cassette that contains the film. You will be asked to hold your breath for a few seconds to generate better images. Then you will be asked to do the same thing, but with your left side against the cassette. The entire test takes no more than 10 to 15 minutes.
Coronary tomography angiogram
How does it work? A coronary CTA comes from a special type of X-ray examination. Patients undergoing a coronary CTA scan receive an iodine-containing contrast dye as an IV solution to ensure the best images possible. The same IV in the arm may be used to give a medication to slow or stabilize the patient's heart rate for better imaging results. During the examination, which usually takes about 10 minutes, X-rays pass through the body and are picked up by special detectors in the scanner. Typically, higher numbers (especially 16 or more) of these detectors result in clearer final images. For that reason, coronary CTA often is referred to as "multidetector" or "multislice" CT scanning. The information collected during the coronary CTA examination is used to identify the coronary arteries and, if present, plaques in their walls with the creation of 3-D images on a computer screen. How is coronary CTA different from other heart tests? One of the most common heart tests is the coronary angiogram, or cardiac catheterization. This test is more invasive and requires more patient recovery time than coronary CTA. Patients who receive coronary angiograms must have a catheter, or small transport tube, threaded into their coronary arteries, which run along the outside of the heart. The catheter typically is inserted into a blood vessel in the upper thigh and then maneuvered up to the coronary arteries. The catheter then is used to inject the iodine dye needed for the test, which uses X-rays to record "movies" of the interior of the coronary arteries. Although coronary CTA examinations are growing in use, coronary angiograms remain the gold standard for detecting coronary artery stenosis, which is a significant narrowing of an artery that could require catheter-based intervention (such as stenting) or surgery (such as bypassing). On the other hand, this new technology has consistently shown the ability to rule out significant narrowing of the major coronary arteries and can noninvasively detect "soft plaque," or fatty matter, in their walls that has not yet hardened but that may lead to future problems without lifestyle changes or medical treatment. Who should consider coronary CTA? Overall, coronary CTA examinations have tended to help determine a lack of significant narrowing and calcium deposits in the coronary arteries, as well as a presence of fatty deposits. This has been found to be particularly valuable in asymptomatic patients with higher risk for coronary disease, in patients with atypical symptoms but lower risk of coronary disease, or in patients with unclear stress-test results. As a result, many physicians advocate the careful use of coronary CTA for patients who have:
Who should not have coronary CTA? To date, coronary CTA has not been proven as effective as the coronary angiogram in detecting disease in the smaller heart arteries that branch off the major coronary arteries. For that reason, many physicians do not consider coronary CTA as an adequate substitute for coronary angiography in patients with strong evidence of narrowing of the coronary arteries. Such patients include those with a history of chest pain during heavy physical activity, a history of positive stress-test results, or a known history of coronary artery disease or heart attack. Coronary CTA also is of limited use in patients with extensive areas of old calcified, or hardened, plaque, which is often the case in older patients. Patients who are extremely overweight or who have abnormal heart rhythms also tend not to be suitable candidates for this test because imaging quality is compromised.
Magnetic resonance imaging
Your doctor uses the MRI to evaluate:
How to prepare: This procedure uses powerful magnets to create its images. For reasons of safety, anyone undergoing a scan should be free of certain metallic or magnetic items. Ask your doctor about whether an MRI scan is advisable for you and for a list of items that should be avoided when having a scan. If you are not claustrophobic, you will not require any sedation, so beforehand you can eat and take your medications as usual. If you are claustrophobic, you may want to ask your doctor to schedule your MRI with sedation. If you do so:
What to expect: An MRI technologist will place small sticky, electrode patches on your chest and back. Men may have their chest partially shaved to help the electrodes stick. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity during the test. Most likely, an intravenous (IV) line will be inserted into a vein in your arm for non-iodine-based contrast (dye) administration. The MRI scanner unit is a long tube that scans the body as you lie on a platform bed. It is fully lighted and ventilated and open at both ends. An intercom system allows you to talk to the scanner operators during the test. You will lie on your back on the scanner bed, with your head and legs elevated for comfort. During the exam, you will be asked to lie as still as possible. The technologist will ask you to hold your breath periodically for short periods to reduce blurring of the images from breathing motion. During scanning, you may hear loud banging noises, which can be muffled with headphones or earplugs you will receive before scanning begins. The MRI scan takes about 30 to 75 minutes, depending on the extent of the imaging needed. After the procedure you may resume your usual activities and normal diet immediately if you did not receive sedation. If you did, someone else should drive you home, and your doctor will give you instructions on when you can eat, drink, and return to normal activities.
Invasive tests
In our section on invasive testing you will find:
Carotid angiography
Your doctor uses carotid angiography to:
To prepare: You can wear whatever you like to the hospital because you will wear a hospital gown during the procedure. Leave all valuables at home. If you normally wear dentures, glasses, or a hearing aid, plan to wear them during the procedure. Your doctor or nurse will give you specific instructions about what you can and cannot eat or drink before the procedure. Ask your doctor what medications should be taken on the day of your test. You may be told to stop certain medications, such as Coumadin (warfarin, a blood thinner). If you are diabetic, ask your physician how to adjust your medications the day of your test. Tell your doctor and/or nurses if you are allergic to anything, especially iodine, shellfish, X-ray dye, or latex or rubber products (such as rubber gloves or balloons). You might not return home the day of your procedure. Bring items with you (such as robe, slippers, and toothbrush) that may make your stay more comfortable. When you are able to leave, arrange for a companion to bring you home. What to expect: You will be given a hospital gown to wear. A nurse will start an intravenous (IV) line in your arm so that medications and fluids can be administered during the procedure. The angiography room is cool and dimly lit. You will lie on a special table. If you look above, you will see a large camera and several TV monitors. The nurse or doctor will clean your skin at the site where the catheter (narrow plastic tube) will be inserted (arm or groin). Sterile drapes are used to cover the site and help prevent infection. It is important that you keep your arms and hands down at your sides and not disturb the drapes. Small, sticky electrode patches will be placed on your chest. The electrodes are attached to an electrocardiograph (EKG) monitor that charts your heart's electrical activity. You will be given a mild sedative to relax you, but you will be awake and conscious during the entire procedure. The doctor will use a local anesthetic to numb the site. A plastic introducer sheath (a short, hollow tube through which the catheter is placed) will be inserted into a blood vessel in your arm or groin. A catheter then is inserted through the sheath and threaded to the arteries of your neck. When the catheter is in place, the lights will be dimmed and a small amount of "contrast material" will be injected through the catheters into your arteries. The contrast material outlines the vessels that provide circulation to your brain. When the contrast material is injected, you may feel hot or flushed for several seconds. This is normal and will go away in a few seconds. Tell the doctor or nurses if you feel an allergic reaction (itching, tightness in the throat), nausea, chest discomfort, or any other symptoms. The X-ray camera will be used to take photographs of the arteries of the head and neck. You may be asked to hold your breath or turn your head in different directions while the X-rays are taken. When all the images have been taken, the catheter will be removed and the lights will be turned on. After the procedure: The catheter and sheath are removed. You will need to be on bed rest for several hours. You will need to drink plenty of liquids to clear the contrast material from your body. You may feel the need to urinate more frequently. Your doctor will tell you if you are able to return home or will need to stay overnight. In either case, you will be monitored for several hours after the procedure. You will need a companion to drive you home. Treatment, including medications, diet, and future procedures will be discussed with you prior to going home. Care of the wound site, activity, and follow-up care will also be discussed.
Intravascular ultrasound
Your doctor uses IVUS to:
To prepare: You can wear whatever you like to the hospital because you will wear a hospital gown during the procedure. Some procedures may require an overnight stay. If you normally wear dentures, glasses or a hearing aid, plan to wear them during the procedure. Your doctor or nurse will give you specific instructions about what you can and cannot eat or drink before the procedure. Ask your doctor what medications should be taken on the day of your test. You may be told to stop certain medications, such as Coumadin (warfarin, a blood thinner) or aspirin. If you have diabetes, ask your physician how to adjust your medications the day of your test. Tell your doctor and/or nurses if you are allergic to anything, especially iodine, shellfish, X-ray dye, or latex or rubber products (such as rubber gloves or balloons), or penicillin-type medications. Arrange for a companion to bring you home. What to expect: You will be given a hospital gown to wear. A nurse will start an intravenous (IV) line in your arm so that medications can be administered during the procedure. You will lie on a special table. The nurse will clean your skin at the groin. Sterile drapes are used to cover the site and help prevent infection. It is important that you keep your arms and hands down at your sides and not disturb the drapes. Small, sticky electrode patches will be placed on your chest. The electrodes are attached to an electrocardiograph (EKG) monitor, which charts your heart's electrical activity. You will be given a mild sedative to relax you, but you will be awake and conscious during the entire procedure. The doctor will use a local anesthetic to numb your groin site. A plastic introducer sheath (short, hollow tube through which the catheter is placed) is inserted in the groin. A catheter (narrow plastic tube) will be inserted through the sheath and threaded to the arteries of your heart. Through the catheter, a wire with an ultrasound tip will be passed into your coronary arteries. Once the catheter is within the coronary artery, a series of cross-sectional pictures of the artery are produced. Tell the doctor or nurses if you feel chest discomfort or any other symptoms during the procedure. The IVUS procedure takes about 60 minutes. After the procedure: The catheters and sheath are removed. Pressure will be placed on leg artery. You will need to lie flat and keep the leg straight for three to six hours to prevent bleeding. A pressure dressing will be applied tightly on the groin. The nurse will check your bandage regularly, but call your nurse if you think you are bleeding (have a wet, warm sensation) or if your toes begin to tingle or feel numb. You may be admitted overnight for observation. The nurse will remove the pressure dressing the morning following your procedure. Your doctor will tell you if you are able to return home or should stay for further treatment. Treatment, including medications and diet, will be discussed with you before going home. Care of the wound site, activity, and follow-up care will also be discussed.
Cardiac catheterization
Your doctor uses cardiac catheterization to:
To prepare: You can wear whatever you like to the hospital because you will wear a hospital gown during the procedure. If you normally wear dentures, glasses, or a hearing aid, plan to wear them during the procedure to assist with communication. Your doctor or nurse will give you specific instructions about what you can and cannot eat or drink before the procedure. Ask your doctor what medications should be taken on the day of your test. You may be told to stop certain medications, such as Coumadin (warfarin, a blood thinner). If you have diabetes, ask your physician how to adjust your medications the day of your test. Tell your doctor and/or nurses if you are allergic to anything, especially iodine, shellfish, X-ray dye, penicillin-type medications, or latex or rubber products (such as rubber gloves or balloons). You might not return home the day of your procedure, so bring items with you (such as robe, slippers, and toothbrush) that will make your stay more comfortable. When you are able to leave, arrange for a companion to bring you home. What to expect: Bring a list of your medications (including over-the-counter) and dosages. When you arrive for your appointment, tell your nurse if you are taking Coumadin (warfarin), Plavix (clopidogrel), diuretics (water pill), or insulin. Also remind the staff if you are allergic to anything, especially iodine, shellfish, X-ray dye, penicillin-type medications, or latex or rubber products (such as rubber gloves or balloons). You will be given a hospital gown to wear. A nurse will start an intravenous (IV) line in your arm so that medications and fluids can be administered during the procedure. The cardiac catheterization room is cool and dimly lit. The air must be kept cool to prevent damage to the X-ray machinery that is used during the procedure. You will be offered warm blankets to make you more comfortable. You will lie on a special table. If you look above, you will see a large camera and several TV monitors. You can watch your cardiac cath on the monitors. The nurse will clean your skin at the site where the catheter (narrow plastic tube) will be inserted (arm or groin). The catheter insertion site may be shaved. Sterile drapes are used to cover the site and help prevent infection. It is important that you keep your arms and hands down at your sides, under the sterile drapes. Small, sticky electrode patches will be placed on your chest. The electrodes are attached to an electrocardiograph (EKG) monitor, which monitors your heart rate and rhythm. You will be given a mild sedative to relax you, but you will be awake and conscious during the entire procedure. In some cases, a urinary catheter may be needed during the procedure. The doctor will use a local anesthetic to numb the site. A plastic introducer sheath (a short, hollow tube through which the catheter is placed) is inserted into a blood vessel in your arm or groin. A catheter will be inserted through the sheath and threaded to the arteries of your heart. You may feel pressure as the introducer sheath or catheter is inserted, but you should not feel pain. Tell the nurse or doctor if you feel any pain. When the catheter is in place, the lights will be dimmed and a small amount of contrast material will be injected through the catheters into your arteries and heart chambers. The contrast material outlines the vessels, valves, and chambers. When the contrast material is injected into your heart, you may feel hot or flushed for several seconds. This is normal and will go away in a few seconds. Tell the doctor or nurses if you feel an allergic reaction (itching, tightness in the throat), nausea, chest discomfort, or any other symptoms. The X-ray camera will be used to take photographs of the arteries and heart chambers. You may be asked to hold your breath while the X-rays are taken. When all the photos have been taken, the catheter will be removed and the lights will be turned on. You may have an interventional procedure (to treat your coronary artery disease) combined with your cardiac catheterization. After the procedure: The catheter and sheath are removed. If the catheter was inserted in the arm, the incision will be bandaged and you will need to keep your arm straight for at least an hour. You will be observed for a few hours to monitor any symptoms or side effects of the procedure. Be sure to tell your nurse if you think you are bleeding (wet, warm sensation) or feel any numbness or tingling in your fingers. If the catheter was inserted at the groin, the incision will be closed with applied pressure, a suture device, or a "plug." A "plug" is a material that works with your body's natural healing processes to seal the artery. You will need to lie flat and keep the leg straight for two to six hours to prevent bleeding (less time if a plug was used). Your head cannot be raised more than 30 degrees (about two pillows high). Do not try to sit or stand. A sterile dressing will be placed on the groin area to protect it from infection. The nurse will check your bandage regularly, but call your nurse if you think you are bleeding (have a wet, warm sensation) or if your toes begin to tingle or feel numb. You will need to drink plenty of liquids to clear the contrast material from your body. You may feel the need to urinate more frequently. This is normal. If you are on bedrest, you will need to use a bedpan or urinal. Your doctor will tell you if you are able to return home or will need to stay overnight. In either case, you will be monitored for several hours after the procedure. Treatment, including medications, diet, and future procedures, will be discussed with you before going home. Care of the wound site, activity, and follow-up care will also be discussed. The cardiac catheterization procedure takes only about 30 minutes, but plan to spend about five to nine hours from the preparation through the recovery time.
Physical exam
What to bring to your doctor visit:
When you describe your symptoms, it is important for you to include:
The doctor will look at your skin for good color, which shows that your body is getting an adequate supply of oxygen-rich blood. Your doctor will also feel your skin for warmth and feel your pulse to check your heart's rate, rhythm, and regularity. Each pulse matches up with a heartbeat that pumps blood into the arteries. The force of the pulse also helps evaluate the amount (strength) of blood flow to different areas of your body. Your doctor will check for swelling, which is a sign that your heart is not pumping efficiently. Your doctor will use a stethoscope to listen closely to the sounds the heart makes with each heartbeat. The doctor can evaluate your heart and valve function and hear your heart's rate and rhythm by listening to your heart sounds. Abnormal sounds include: Murmur, an abnormal whooshing sound made by blood flowing abnormally through the heart. This may indicate a leaky heart valve. Click, an abnormal sound made by a valve that is stiff or stenotic. Your doctor will also measure your blood pressure. This is the force or pressure exerted in the arteries by the blood as it is pumped around the body by the heart. It is recorded as two measurements: systolic pressure in the arteries during the period of the heart's contraction (the higher number), and diastolic pressure in the arteries when the heart is relaxed between heartbeats (the lower number). Normal blood pressure for an adult, relaxed and at rest, is less than 140/90. Your age, the condition of your heart, your emotions, medications, and whether you are active or at rest all can affect your blood pressure. One high reading does not mean you have high blood pressure. It may be necessary to measure your BP at several different times to find out your typical value.
Treatment
In this section on treatment you will find:
Nonsurgical options
Conventional balloon angioplasty: In this procedure, blocked coronary arteries are reopened by inflating a tiny balloon inside the blockage, compressing the fatty plaque against the artery walls and widening (dilating) the vessel. Angioplasty with stenting: In most cases, angioplasty is generally combined with a procedure called stenting, in which a tiny tube of metal mesh, or stent, is used as a scaffold to help keep the artery open. It usually is placed over an angioplasty balloon, and the assembly is pushed into a narrowed artery and the balloon is inflated, expanding the stent. The balloon is then deflated and withdrawn. Over a period of several weeks your artery heals around the stent. Stents, too, can become blocked. However, stents coated with a drug—called drug eluting stents—discourage reblocking, or restenosis. These have restenosis rates of less than 10 percent. Almost all stents implanted now are drug-coated. Other drugs have been developed to stop reblocking before it starts. As one of the initiating steps in restenosis, platelets (tiny particles in the blood) collect at the site and promote clotting (thrombosis). Drugs called glycoprotein IIb/IIIa inhibitors block the chemical that encourages the platelets to collect. The glycoprotein IIb/IIIa inhibitors may be given intravenously (IV) just before the intervention and then continuously for a period of time, depending on which is used. Angioplasty, with or without stenting, is often raised as a treatment possibility even before a diagnostic catheterization, so that the diagnostic procedure can proceed directly to treatment while you are in the cath lab, if warranted. Also, angioplasty and stenting may be combined with the use of other specialized procedures or catheters, including: Rotoblation (percutaneous transluminal rotational atherectomy, or PCRA): In this procedure, a special catheter with an acorn-shaped diamond-coated tip is guided to the narrowing in your coronary artery. The tip spins at a high speed and grinds up the plaque on your arterial walls. The microscopic particles are safely washed away in your blood stream and filtered out by your liver and spleen. Cutting balloon: A balloon tip with small blades is inserted through the catheter and moved to the narrowing in the artery. When the balloon is inflated, the blades are activated. After the small blades score the plaque, the balloon compresses the fatty matter into the artery wall. Although the above treatments are considered nonsurgical, they entail risks and require special expertise. Ask your doctor and hospital how many such procedures they perform each year. According to American Heart Association guidelines published in 2001, hospitals should perform at least 400 percutaneous coronary interventional (PCI) procedures each year. Learn more about what to expect and the recovery process.
What to expect
Once the catheter is placed into the narrowed artery, the doctor will perform the interventional procedure. The procedure usually lasts about 1 1/2 to 2 1/2 hours, but preparation and recovery time add several hours. Patients typically stay overnight in the hospital. Recovery: Your doctor will discuss with you when you can resume your normal activities. Generally, however, you will need to take it easy for a few days after returning home: Avoid heavy lifting or any other strenuous activities. You may climb stairs, but you'll want to climb more slowly than usual. Gradually increase your activities until you have returned to your normal level of activity by the end of one week. Carry nitroglycerin for the first six months. Be sure it is fresh. If your symptoms return, alert your doctor immediately. Angina that feels like the angina you had before your procedure might be a warning that your coronary artery has reblocked or that you have new blockages in other arteries. Other symptoms might include discomfort in your chest or in any other area where your previous pain occurred, excessive shortness of breath, dizziness, irregular heartbeats, nausea, excessive sweating, or inability to perform normal daily activities without becoming overtired or exhausted.
Surgical options
The goals of bypass surgery are to relieve symptoms of coronary artery disease, including angina, and to lower the risk of a heart attack or other heart problems. The surgery generally lasts from three to five hours, depending on the number of arteries being bypassed. In this section on bypass surgery you will find information on:
Procedures
Minimally invasive direct coronary artery bypass (MIDCAB) surgery: Before your surgery, your doctor will review all your diagnostic tests to decide whether you are a candidate for minimally invasive direct bypass surgery, which involves smaller incisions and does not require the rib cage to be opened. In some patients, MIDCAB surgery can be performed through a small incision in the thorax. And newer robotic techniques are allowing surgeons to perform bypass surgery through even smaller keyhole incisions. The benefits of minimally invasive direct bypass surgery include:
Off-pump or beating-heart bypass surgery: This procedure allows surgeons to work on the heart while it is still beating. The heart-lung machine is not used. The surgeon uses advanced operating equipment to stabilize (hold) portions of the heart and bypass the blocked artery in a highly controlled operative environment. Meanwhile, the rest of the heart keeps pumping and circulating blood to the body.
Bypass grafts
Internal mammary arteries (thoracic arteries, IMA grafts): The internal mammary artery is the most commonly used vessel for bypass grafts because it has proven to remain patent or open the longest and has thus produced the best long-term results. The arteries usually can remain attached at one end and the free end can then be attached to the blocked coronary artery just below the obstructed area. If the surgeon completely detaches the mammary artery at both ends, it is called a "free" mammary artery. Over the past decade, more than 90 percent of all patients have received at least one internal mammary artery graft. Radial artery: The radial artery is the second most commonly used arterial graft. The arm has two arteries, the ulnar and radial arteries. Most people receive blood to their arm from the ulnar artery and will not have any side effects if the radial artery is used. Careful preoperative and intraoperative tests determine if the radial artery can be used. If you have certain conditions (such as Raynaud's, carpal tunnel syndrome, or painful fingers in cold air) you may not be a candidate for this type of bypass graft. The radial artery incision is in your forearm, about 2 inches from your elbow and ending about 1 inch from your wrist. After this type of bypass, patients are routinely placed on a medication called a "calcium channel blocker" for about six months after surgery to help keep the radial artery widely open. The gastroepiploic artery to the stomach and the inferior epigastric artery to the abdominal wall are less commonly used for grafting. Saphenous veins: These veins are removed from your leg, then sewn from your aorta to the coronary artery below the site of blockage. To bypass the blockage, the surgeon makes a small opening just below the blockage in the diseased coronary artery. The graft is sewn into the opening, redirecting the blood flow around this blockage. If a saphenous (leg) or radial (arm) vein is used, one end is connected to the coronary artery and the other to the aorta. If a free mammary artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The procedure is repeated until all affected coronary arteries are treated. It is common for three or four coronary arteries to be bypassed during surgery. A note about minimally invasive vein removal: Minimally invasive saphenous vein removal is accomplished by a small incision in the groin and one to two 1-inch incisions in the leg, near the knee. The surgeon uses special instruments to delicately remove the vein and close the incision with little blood loss and small risk of infection. Removing the saphenous vein by this method reduces patient discomfort and results in smaller scars and a quicker recovery.
Recovery
The patient is transferred to an intensive care unit for close monitoring for about one to two days after the surgery. The monitoring during recovery includes frequent checks of vital signs and other parameters, such as heart sounds and oxygen and carbon dioxide levels in arterial blood. Once the patient is transferred to the nursing unit, the hospital stay is about three to five more days. Recovery: Your medical team will provide you with information about your recovery, including how to care for your incision, as well as guidelines for returning to work and your other activities. Generally, however, full recovery takes two to three months. Coronary artery bypass graft surgery does not prevent coronary artery disease from recurring. Lifestyle changes and prescribed medications can reduce the risk. Lifestyle changes include quitting smoking; exercising most days; taking off pounds if you are overweight; sticking to a diet low in fats and trans fats; treating high cholesterol and LDL; carefully managing any diabetes with strict adherence to diet and medications; keeping your blood pressure within normal levels; taking prescribed medications as directed; and following up with your doctor for regular office visits.
Managing
Cholesterol control The biggest single difference between preventing first-time heart problems and managing known CAD is the emphasis your physician will place on pushing down your LDL cholesterol—the "bad" kind. The goal is achieving a level below 100 milligrams per deciliter (mg/dL). Even lower is better. For someone at very high risk because of diabetes, a previous heart attack, or other risk factors, the target for LDL was changed in 2004 by an advisory panel to below 70 mg/dL. To push down LDL, most people in secondary prevention automatically are given a statin drug, which blocks production of a liver enzyme that the body uses to manufacture cholesterol. Indeed, many physicians believe in starting secondary-prevention patients at a high dose to push down their LDL quickly. (Studies also have found that a large percentage of patients who start at a low dose never get raised to a higher one, because they—or their doctor—don't follow up.) Statins also raise HDL cholesterol to some extent. HDL cholesterol, the "good" kind, acts to remove LDL cholesterol from the body as well as C-reactive protein (a measure of inflammation in the blood) so is thought to protect against heart disease. A small number of people placed on a statin experience side effects, such as initial or lasting muscle or joint discomfort or weakness, and the incidence of such side effects tends to rise at higher doses. In a very small number of people, the problems are so severe that they are temporarily or even permanently incapacitated. Generally speaking, the higher the dose, the greater the likelihood of side effects, so people need to be particularly tuned in to the signals their body might send, and report any difficulties to their physician. The dose might need to be adjusted, or switching to another statin might eliminate the problem. Because statins interfere with the liver's production of a particular enzyme, your blood will need to be checked every three to six months to be on guard for changes in liver function. Statins do not take the place of diet and lifestyle changes to lower your cholesterol. You may need to take a statin for the rest of your life. Based on your full lipid profile, your doctor may want to try other drugs that optimize your LDL, HDL, and triglyceride levels. Clot control A daily low dose of aspirin—a baby aspirin or half an adult aspirin—dramatically reduces the incidence of angina and heart attacks, and is now routinely prescribed for people in secondary prevention. The conventional explanation is that the aspirin reduces clotting, although how such a low dose has that effect has long been unclear. Researchers now suspect that its more important effect is to interfere with the inflammatory process that is part of ongoing CAD. A baby aspirin or half of an adult aspirin is recommended. If you have had recurring heart attacks or strokes, your physician may prescribe a powerful anticoagulant, or blood thinner, such as warfarin, to prevent clotting. In some patients, aspirin may be contraindicated so it is important to speak to your doctor before starting aspirin therapy. Besides drugs Your physician will also ask you to reduce your risks by changing the way you live, emphasizing good habits and discouraging bad ones. The National Cholesterol Education Program administered by the federal government refers to this effort as therapeutic lifestyle changes (TLC), and considers TLC the first line of defense for people in primary prevention. For you, however, TLC is but one weapon, albeit an important one, in a larger arsenal. Among the big guns in TLC, the most powerful is to quit smoking. Even a single cigarette a day significantly raises the risk of a heart attack. But other changes are important, too:
In some cases, lifestyle changes and medications are not enough to treat your coronary artery disease, and interventional or surgical therapies may be required to prevent damage to your heart. The treatment section has more information on these therapies. The section on preventing CAD has more information and advice concerning smoking, diet, exercise, and weight control. |