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Lifespan's A - Z Health Information Library |
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  Heart attack and acute coronary syndromeHighlightsDrug Approval In 2006, the FDA approved the use of clopidogrel (Plavix) for patients who have had a STEMI heart attack and who will not be having angioplasty. A STEMI is a very severe type of heart attack caused by sudden and total artery blockage. Angioplasty and Stents Surgery with angioplasty and stents that is performed more than 3 days after a heart attack offers no advantage over standard drug therapy for clinically stable patients, indicates an important 2006 New England Journal of Medicine study. Experts recommend that this procedure be performed to open blocked arteries within 12 hours of a heart attack. Drug-Coated Stents
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) NSAIDs such as acetaminophen (Tylenol), ibuprofen (Advil) should be used with caution by patients who have had a heart attack:
IntroductionThe heart is the human body's hardest working organ. Throughout life it continuously pumps blood enriched with oxygen and vital nutrients through a network of arteries to all parts of the body's tissues. In order to perform the arduous task of pumping blood to the rest of the body, the heart muscle itself needs a plentiful supply of oxygen-rich blood, which is provided through a network of coronary arteries. These arteries carry oxygen-rich blood to the heart's muscular walls (the myocardium).  Coronary Artery DiseaseCoronary artery disease is the most common cause of heart attacks. Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). This causes blockage of arteries (ischemia) and prevents oxygen-rich blood from reaching the heart. A full-blown heart attack occurs when blood flow to the myocardium is blocked and tissue death occurs from loss of oxygen, severely damaging the heart. The medical term for heart attack is myocardial infarction. [For more information see In-Depth Report #3: Coronary artery disease.]  Click the icon to see an image of atherosclerosis. Heart AttackHeart attack (or myocardial infarction) is the most serious outcome of atherosclerosis. It can occur as a result of one or two effects of atherosclerosis: (1) If the artery becomes completely blocked and ischemia becomes so extensive that oxygen-bearing tissues around the heart die. (2) If the plaque itself develops fissures or tears. Blood platelets adhere to the site to seal off the plaque, and a blood clot (thrombus) forms. A heart attack can then occur if the formed blood clot completely blocks the passage of oxygen-rich blood to the heart.  Click the icon to see an image of an acute myocardial infarction. AnginaAngina is the primary symptom of coronary artery disease and is typically experienced as chest pain. There are two kinds of angina:
Acute Coronary SyndromeAcute coronary syndrome (ACS) is a severe and sudden heart condition that requires aggressive treatment, but has not developed into a full blown heart attack. Acute coronary syndrome includes:
SymptomsANYONE WHO BELIEVES THEY ARE HAVING A HEART ATTACK SHOULD IMMEDIATELY CALL THE EMERGENCY MEDICAL SYSTEM (911 IN THE UNITED STATES). In people with known heart disease, any unusual chest pain or other symptoms of heart attack that do not clear up with medications are signals to go to the hospital. The degree of pain and the specific symptoms before a heart attack vary greatly among individuals. Onset can be abrupt, gradual, or intermittent. Heart Attack SymptomsChest Pain. People with heart disease or risk factors should be concerned about any chest pain, usually precipitated by exercise or stress, that interrupts normal activities and does not clear up after resting or taking angina medications. Chest symptoms might be experienced as follows:
Although chest pain is the classic symptom, it occurs in only about half of patients with a heart attack. Other Common Symptoms. Other common symptoms of a heart attack include:
Uncommon Symptoms. Some studies suggest that nearly half of patients with heart attack do not have chest pain as the primary symptom. Common atypical symptoms of a heart attack include:
Patients most likely to have atypical symptoms are women and the very elderly (although they can certainly have classic heart attack symptoms as well.)
Symptoms That Are Less Likely to Indicate a Heart Attack. The following are symptoms that are more likely to be due to causes other than a heart event:
The presence of these symptoms, however, does not always rule out a serious heart event. Ruling Out Other Causes of SymptomsChest pain is a very common symptom in the emergency room, but heart problems account for only 10% to a third of all episodes. High on the list of other causes of chest pain are the following:
What To Do When You Have Symptoms of a Heart AttackImmediately call 911 or the local emergency number. If patients have been previously diagnosed with angina, they should take one nitroglycerin dose either as an under-the-tongue tablet or in spray form at the onset of symptoms. They should take another dose every 5 minutes up to three doses or when the pain is relieved, whichever comes first. It should be noted, however, that only 20% of heart attacks occur in patients with long-standing angina. Anyone who has heart disease or risk factors for it and experiences heart attack symptoms should immediately contact emergency services. The patient should chew an aspirin (250 - 500 mg) and be sure that emergency health providers are informed of this so an additional dose is not given. Patients who experience chest pain should go immediately to the nearest emergency room, preferably traveling by ambulance. They should not drive themselves. PrognosisEach year, an estimated 650,000 Americans will suffer a first heart attack, and 450,000 will have a recurrent episode. Currently, half of the men and 63% of the women who died of heart disease had no warning prior to their fatal attacks. Predicting the Severity of a Heart AttackHeart attacks may be rapidly fatal, evolve into a chronic disabling condition, or lead to full recovery. The long-term prognosis for both length and quality of life after a heart attack depends on its severity and the preventive measures taken afterward. About 88% of patients under age 65 who experience a heart attack can expect to return to work. About 12,600,000 Americans who have had heart attacks, angina, or both are alive today. However, within 6 years of a heart attack, 18% of men and 35% of women have a recurrent attack. And, about 22% of men and 46% of women develop heart failure. Although no tests can absolutely predict whether another heart attack will occur, experts estimate that up to 30% of fatal attacks, and many follow-up surgeries, could be avoided with healthy lifestyle changes and adherence to medical treatments. Two-thirds of patients who have suffered a heart attack, however, do not take the necessary steps to prevent another. Higher Risk Individuals. A heart attack is always more serious in certain people:
Women are more likely to die after a heart attack than men. The risk is highest in younger women (although in the younger population, the risk for having a first heart attack and then dying from it is very low). It is still unclear why heart attacks are more severe in this group. Factors Occurring at the Time of a Heart Attack That Increase Severity. The presence of other conditions during a heart attack can contribute to a poorer outlook:
Risk for StrokeHeart attacks and acute coronary syndrome pose a high risk for stroke. According to a major 2002 study, the risk for stroke after heart attack is 2.5% in the first 6 months and 5% per year thereafter. In the study, patients with a higher risk (about 4%) for stroke within 6 months of a heart attack were older (over age 75), African-American, had a history of stroke, atrial fibrillation, hypertension, diabetes, or peripheral artery disease. Most people who fall into these categories have more than one of these risk factors. Risk FactorsAbout 25% of all Americans have one or more risk factors for heart disease, increasing their risk for heart attack. Most risk factors for heart disease are related to lifestyle. Some risk factors, (such as age, gender, and ethnicity) cannot be changed. Nevertheless, overall risks can be reduced with healthy lifestyle changes. [For more information on heart disease, see In-Depth Report #3: Coronary artery disease.]
Nonmodifiable Risk FactorsAge. About 85% of people who die from heart disease are over the age of 65. Gender. Coronary artery disease and heart attacks are much more common in middle-aged men. Women have, on average, 10 - 15 more years of heart disease-free life than do men, but as women age, they catch up to men. Women are more likely to have angina than men are. Younger women with heart disease often do not have the same symptoms as their male counterparts and may be less likely to be diagnosed correctly. They are also more likely than men are to die after a heart attack. Evidence suggests that this is because women tend to be older and sicker than men at the time of a first attack. A 2002 study indicated, however, that with early aggressive treatment women with acute coronary syndrome do as well or better than men with the same condition and treatments. Ethnicity. Of all major ethnic groups, African-American women face the highest risk for death from heart disease, and their rate of heart attacks is increasing. (Mortality rates in men do not differ much by race.) Native American men have a lower risk for heart disease than Caucasian men, and Hispanics have the lowest risk for heart disease of all major American population groups. Timing of Heart Attack. A 2007 study suggested that patients who are admitted to a hospital on a weekend are less likely to receive aggressive heart attack treatment and less likely to survive than patients who are treated on a weekday. However, no one can predict when a heart attack will occur. The most important point is to get treatment quickly, regardless of the day of the week. And, if you think you having a heart attack, call an ambulance -- or have someone call for you -- to ensure prompt treatment. Do not drive yourself. Cholesterol and Other LipidsCholesterol. Cholesterol is a white, powdery substance that is found in all animal cells and in animal-based foods (not in plants). In spite of its bad press, cholesterol is an essential nutrient necessary for many functions. However, when certain cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol. Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol responsible for many heart problems. Triglycerides are another type of lipid (fat molecule) that can be bad for the heart. High-density lipoprotein (HDL) cholesterol is the "good" cholesterol that helps protect against heart disease. Doctors test for a "total cholesterol" profile that includes measurements for LDL, HDL, and triglycerides. The ratio of these lipids can affect heart disease risk. [For more information, see In-Depth Report #23: Cholesterol.] Cholesterol Goals. In 2004, the National Cholesterol Education Program updated its clinical practice guidelines. The new recommendations set lower treatment goals for LDL levels based on a patient's risk factors for heart disease. These risk factors include:
Having two or more of these risk factors indicates a greater than 20% chance of having a heart attack within 10 years.
LDL cholesterol, together with other risk factors for heart disease, is the best determinant for whether cholesterol therapy is needed and whether it is working properly. In particular, the new guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes.
Other Lipids. Elevated levels of other fatty molecules (lipids) are also now thought to be important indicators of heart disease risk. Studies are finding an elevated risk for angina and first heart attacks in people with elevated levels of lipoprotein(a), or lp(a). This lipoprotein falls somewhere in density between HDL and LDL and may have some properties that increase the risk for blood clots. Some experts suggest, however, that high levels of lp(a) may merely be markers of late-stage atherosclerosis, not a cause. High Blood PressureHigh blood pressure, or hypertension, has long been a proven cause of coronary artery disease. Blood pressure is categorized as normal, prehypertensive, and hypertensive (which is further divided as Stage 1 or 2 according to severity). High blood pressure is generally considered to be a blood pressure reading greater than or equal to 140 mm Hg (systolic) or greater than or equal to 90 mm Hg (diastolic). Blood pressure readings in the prehypertension category (120 - 139 systolic or 80 - 89 diastolic) indicate an increased risk for developing hypertension. [See Table Blood Pressure Ranges.] A normal blood pressure reading is 120/80 mm Hg or lower. Most people with high blood pressure should aim for a goal of below 140/90 mm Hg. Patients with certain health problems should aim lower (blood pressure in patients with kidney disease, heart failure, or diabetes should be equal to or lower than 130/80 mm Hg.) [For more information, see In-Depth Report #14: High blood pressure.]
Obesity and Metabolic SyndromeAmerican obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels are usually high while HDL (beneficial cholesterol) levels tend to be low, both risk factors for heart disease. Obesity, in any case, has other effects (hypertension, increase in inflammation) that pose major risks to the heart. Obesity is particularly hazardous when it is one of the components of the metabolic syndrome. This syndrome is diagnosed when three of the following are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Obesity is highly linked with type 2 diabetes, in any case. And diabetes itself poses a significant risk for high cholesterol levels and heart disease. [For more information, see In-Depth Report #53: Weight control and diet.] Sedentary Lifestyle and ExercisePeople who are sedentary are almost twice as likely to suffer heart attacks as are people who exercise regularly. Exercise has several effects that benefit the heart and circulation, including improving cholesterol and lipid levels, reducing inflammation in the arteries, assisting weight loss programs, and helping to keep blood vessels flexible and open. Studies continue to show that physical activity and avoiding high-fat foods are the two most successful means of reaching and maintaining heart healthy levels of fitness and weight. Experts have been attempting to define how much exercise is needed to produce heart benefits. In 2002, a well-conducted study on overweight adults confirmed previous research that reported beneficial changes in cholesterol and lipid levels even when people performed low amounts of moderate or high intensity exercise (walking or jogging 12 miles a week). However, more intense exercise is required to significantly change cholesterol levels, notably by increasing HDL (the so-called good cholesterol). Overweight people who have trouble losing pounds can still achieve considerable heart benefits by exercising. Resistance (weight) training has also been associated with heart protection. Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina. Some studies suggest that people may gain the greatest heart protection benefit from the total daily amount of energy they expend, rather than from the length of a single exercise session. Therefore, the best way to exercise may be in multiple short bouts of intense exercise, which can be particularly helpful for older people. Sudden strenuous exercise (such as snow shoveling and mowing lawns) can put people at risk for angina and heart attack. Activities that involve raising the arms above the head may also be risky. Patients with angina should never exercise shortly after eating. People with risk factors for heart disease should seek medical clearance and a detailed exercise prescription. And all people, including healthy individuals, should listen carefully to their bodies for signs of distress as they exercise. [See In-Depth Report #29: Exercise.] Diabetes and Insulin ResistanceHeart disease and stroke are the leading causes of death in people with diabetes. People with diabetes are at risk for the following heart-risk conditions, and the more of these conditions they have, the worse the outlook:
Patients with both diabetes and heart disease may have a higher risk for silent ischemia, a condition in which people have blocked arteries but do not experience the angina, the chest pain that signals heart disease [For more information, see In-Depth Reports #9: Diabetes - type 1 or #60: Diabetes - type 2.] SmokingSmokers in their 30s and 40s have a heart-attack rate that is five times higher than their nonsmoking peers. Cigarette smoking may be directly responsible for at least 20% of all deaths from heart disease, or about 120,000 deaths annually. Smoking cigars may increase the risk of early death from heart disease, although evidence is much stronger for cigarette smoking. Although heavy cigarette smokers are at greatest risk, a 2002 study suggested that people who smoke as few as three cigarettes a day are at higher risk for blood vessel abnormalities that endanger the heart. Regular exposure to passive smoke also increases the risk of heart disease in nonsmokers. [For more information, see In-Depth Report #41: Smoking.] Eating HabitsEating habits can either protect or hurt the heart. Experts generally agree on the following heart-smart recommendations:
After starting any heart healthy diet, it generally takes an average of 3 - 6 months before any noticeable reduction in cholesterol occurs, although some people have reported better levels in as few as 4 weeks. An intensive program may be necessary to achieve significant improvements in cholesterol levels and to reduce other heart risk factors. [For more information, see In-Depth Report #43: Heart-healthy diet.] Stress and Psychologic FactorsStress. The effects of mental stress on heart disease are controversial. Stress can affect the heart when it activates the sympathetic nervous system (the automatic part of the nervous system that affects many organs, including the heart). Some studies suggest an association between acute stress and a higher risk for serious cardiac events, such as heart rhythm abnormalities and heart attacks, in people with heart disease. However, not all studies report strong evidence that stress has any effect on the heart, particularly in people without any history of heart disease. [See In-Depth Report #31: Stress.] Depression. Depression increases the severity of heart attack and may even impair a patient's response to medication for heart disease. Although people with heart disease may certainly become depressed, this does not explain entirely the link between the two problems. The data now suggest that depression itself may be a true risk factor for heart disease as well as its increased severity. Several studies have suggested that depression has biologic effects on the heart, including blood clotting and heart rate. A study in 2001, for example, reported an association between depression and a greater risk for death from heart problems even in people without a history of heart disease. A 2002 study reported a higher risk for heart failure in women -- although not in men -- with depression. The more severe the depression, the more dangerous to the health, although even mild depression, including feelings of hopelessness, experienced over many years, may harm the heart, even in people with no early signs of heart disease. [See In-Depth Report #8: Depression.] AlcoholBenefits of Moderate Drinking. Several studies have found heart protection from moderate intake of alcohol (one or two glasses a day). Moderate alcohol consumption can help boost HDL levels. Alcohol may also prevent blood clots and inflammation. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit. Adverse Effects of Heavy Drinking on the Heart. By contrast, heavy drinking harms the heart; heart disease is the leading cause of death in alcoholics. Evidence suggests that people who consume more than three drinks a day have abnormal blood clotting factors. Heavy alcohol consumption can raise blood pressure, and binge drinking may increase the risk for hemorrhagic stroke (caused by bleeding in the brain). Large doses of alcohol can trigger irregular heartbeats, which can be dangerous in people with existing heart disease. Pregnant women and people who can't drink moderately should not drink at all. NSAIDs and COX-2 InhibitorsIn 2005, the FDA warned that all nonsteroidal anti-inflammatory drugs (NSAIDs) -- with the exception of aspirin -- carry heart risks. NSAIDs and COX-2 inhibitors may increase the risk for death in patients who have experienced a heart attack. The risk is greatest at higher dosages, but not necessarily for length of time. According to a 2006 Danish study of heart attack survivors, patients do not need to take NSAIDs for long periods of time to be at risk. NSAIDs include nonprescription drugs like ibuprofen (Advil, Motrin) and prescription drugs like diclofenac (Cataflam, Voltaren). Celecoxib (Celebrex) is currently the only COX-2 inhibitor that is available in the U.S. It has been linked to cardiovascular risks such as heart attack and stroke. Patients who have had heart attacks should talk to their doctors before taking any of these drugs. A 2006 comprehensive report from the U.S. Agency for Healthcare Quality and Research indicated that both NSAIDs and COX-2 inhibitors pose similar risks for heart attacks. The report found that one particular NSAID, naproxen (Aleve, Naprosyn), may present less risk of heart attack for some patients, but other studies have contradicted this finding. A 2006 Journal of the American Medical Association study suggested that diclofenac (Voltaren, Cataflam) poses a higher risk for heart attack than other NSAIDs. In 2007, the American Heart Association issued a scientific statement encouraging doctors to change the way they prescribe pain relief medication for patients with or who are at risk for heart disease. The AHA recommends that patients first try non-drug methods of pain relief (physical therapy, exercise, weight loss to reduce stress on joints, and heat or cold therapy). If these methods don’t work, patients should take the lowest possible dose of acetaminophen (Tylenol) or aspirin. COX-2 inhibitors, such as celecoxib (Celebrex), should be the last resort. Other Risk FactorsAnemia. Anemia has adverse effects on the heart and increases the severity of cardiac conditions, including heart failure and heart attacks. Iron Overload. An inherited disease called hemochromatosis, in which the intestinal tract absorbs too much iron from food, has been associated with atherosclerosis and heart attack. About 10% of Caucasians carry the gene. There is no strong evidence that excess iron levels in people without hemochromatosis can contribute to heart disease. Sleep Apnea. Obstructive sleep apnea is a condition in which tissues in the upper throat collapse at intervals during sleep, thereby blocking the passage of air. It has been strongly associated with high blood pressure and obesity, but is also associated with heart disease and heart attacks, regardless of these risk factors. Some evidence suggests that obstructive apneas cause an increase in stiffness and inflammation in the arteries. Pregnancy Complications. Although women of child-bearing age are generally at low risk of heart attack, pregnancy can increase the risk for women with certain health conditions. Pregnant women who have diabetes, high blood pressure, or coronary artery disease are at greater risk of having a heart attack than healthy pregnant women. Smoking can increase the risk of heart attack during pregnancy by eight times. Pregnant women who are over 40 years old are at much greater risk than younger women. DiagnosisWhen a patient comes to the hospital with chest pain, the following diagnostic steps are usually taken to determine any heart problems, and, if present, their severity.
Electrocardiogram (ECG)An electrocardiogram (ECG or EKG) measures and records the electrical activity of the heart. The waves measured by the ECG correspond to the contraction and relaxation pattern of the different parts of the heart. Specific waves seen on an ECG are named with letters: 
 Click the icon to see an image of a normal sinus rhythm. Doctors use a term called the P-Q or P-R interval, which is the time taken for an electrical impulse to travel from the atria to the ventricle. The most important wave patterns in diagnosing and determining treatment for a heart attack are called ST elevations and Q waves. Elevated ST Segments: Heart Attack. Elevated ST segments are strong indicators of a heart attack in patients with symptoms and other indicators. They suggest that an artery to the heart is blocked and that the full thickness of the heart muscle is damaged. When this finding coincides with a heart attack, the condition is sometimes referred to as either as a Q-wave myocardial infarction or a STEMI (ST-segment elevation myocardial infarction). STEMI heart attacks are very severe and usually have complete artery blockage. ST-elevations are strong indicators for aggressive treatments (thrombolytic drugs or angioplasty) to reopen blood vessels. (ST segment elevations do not always mean the patient has a heart attack. Also, some patients do not have elevated ST segments. Other factors are important in making a diagnosis.) Non-Elevated ST Segments: Angina and Acute Coronary Syndrome. A depressed or horizontal ST wave suggests some blockage and the presence of a heart disease, even if there is no angina present. It occurs in about half of patients with other signs of a heart event. This finding, however, is not very accurate, particularly in women, and can occur without heart problems. In such cases, laboratory tests are needed to determine the extent, if any, of heart damage. In general, one of the following conditions may be present:
EchocardiogramAn echocardiogram is a noninvasive test that uses ultrasound images of the heart. This test is more expensive than an ECG, but it can be very valuable, particularly when used with an exercise stress test, to detect the location and extent of heart muscle damage. Nuclear Ventriculography (Thallium Stress Test)Nuclear ventriculography (also known as a radionuclide test) uses radioactive materials called tracers to make heart chambers and blood vessels visible. The procedure is noninvasive. It is a reliable measure of severe heart events and can help identify if damage has occurred from a heart attack. A radioactive isotope such as thallium (or technetium) is injected into the patient's vein. The radioactive isotope attaches to red blood cells and passes through the heart in the circulating blood. The isotope can then be traced through the heart using special cameras or scanners. The images may be combined with an electrocardiogram. The patient is tested while resting, then tested again during an exercise stress test. If the scan detects damage, more images are taken 3 or 4 hours later. Damage due to a prior heart attack will persist when the heart scan is repeated. Injury caused by angina, however, will have resolved by that time. AngiographyAngiography is an invasive test. It is used for patients who show strong evidence for severe obstruction on stress and other tests and for patients with acute coronary syndrome.
 Click the icon to see an image of cardiac catheterization.  Click the icon to see an image of dye injected into the coronary arteries. Major complications include stroke, heart attacks, and kidney damage. These risks are very low (about 0.1%), however, if the procedure is done in an experienced medical center (one that performs at least 300 of these operations every year). Allergic reactions can also occur. The procedure is expensive, and between 10 - 30% of patients who have this procedure have normal results. Magnetic Resonance Angiography (MRA). MRA is a very promising noninvasive imaging technique that can provide three-dimensional images of the major arteries to the heart and identify disease with high accuracy. Experts believe this approach will eventually be a good alternative to angiography. Kidney TestsTests that measure kidney function can help predict which patients are at greatest risk of heart attack, stroke, or death from heart disease. Kidney tests measure proteins in the blood that are filtered through the kidneys. These proteins include creatinine and blood urea nitrogen (BUN). A more recent type of kidney test measures the protein cystatin C. Recent research suggests that the cystatin C kidney test may be better at predicting cardiovascular risks in elderly patients. Biologic MarkersWhen heart cells become damaged, they release different enzymes and other molecules into the blood stream. Elevated levels of such markers of heart damage in the blood or urine may help predict a heart attack in patients with severe chest pain and help determine treatment. Some markers include:
Several 2006 studies that evaluated how well biomarkers predict the risk of heart events concluded that they do not provide much more useful information than standard risk factors (high blood pressure, unhealthy cholesterol levels, diabetes). At this time, most experts feel that these standard disease risk factors provide the best predictors of the likelihood of developing coronary artery disease, heart attack, or stroke. TreatmentTreatment options will depend on whether the patient has angina, acute coronary syndrome, or a full-blown heart attack. Patients who are diagnosed with acute coronary syndrome (ACS) may be at risk for a heart attack. ACS refers to either unstable angina or NSTEMI (non ST-segment elevation myocardial infarction). Unstable angina is potentially serious and chest pain is persistent, but blood tests do not show markers for heart attack. With NSTEMI, the blood tests suggest a developing heart attack, but most likely, injury in the arteries is less serious than with a full-blown heart attack. Doctors use a patient's medical history, various tests, and the presence of certain factors to help predict which ACS patients are most at risk for developing a more serious condition. The degree of chest pain itself is not necessarily useful for determining the actual damage in the heart. Depending on how severe the condition is, the patient is then given either medical treatments or more invasive approaches, such as angioplasty. Some experts believe that even if patients with ACS are only given drug therapy, they should still be transferred to centers equipped for angioplasty. Immediate Treatments to Support the PatientEarly supportive treatments are similar for patients who have ACS or those who have had a heart attack. Oxygen. Oxygen is almost always administered right away, usually through a tube that enters through the nose. The patient is given aspirin if one was not taken at home. Medications for Relieving Symptoms.
Anticlotting Medications. Appropriate anticlotting medications are started immediately in all patients.
Opening the Arteries: Thrombolytic Drugs or Emergency Angioplasty (PTCA)After a heart attack, clots form in the injured artery within 4 - 6 hours in 90% of patients. Opening a clotted artery as quickly as possible is the best approach to improving survival. The standard medical and surgical solutions for opening arteries are:
The best candidates for either thrombolytic therapy or angioplasty are:
Specific Candidates for Emergency Angioplasty. Most patients who meet the criteria for either thrombolytic drugs or angioplasty do better with angioplasty (although only in centers equipped to do this procedure). Good candidates for angioplasty include:
As with thrombolytic treatments, angioplasty is most effective when performed within 12 hours of symptoms, and the sooner the better. Unfortunately not all communities have centers experienced in the procedure. The experience of the medical center's staff is critical for optimal benefits, and not all surgeons are experienced in angioplasty. However, the procedure is becoming increasingly available, and overall mortality rates are improving over time with angioplasty. Patients or their families should be sure their surgeon has performed at least 75 of these procedures and that the medical center has performed at least 200. Specific Candidates or Non-Candidates for Thrombolytics. People who meet the criteria for either thrombolytics or angioplasty may benefit from thrombolytic drugs even if they have high-risk conditions such as diabetes, high systolic blood pressure less than 180 mm Hg, or a history of heart attack. Several studies report that women do worse after thrombolytic therapy. Evidence indicates, however, that they are generally older and have more serious medical conditions when they seek treatment. One study also reported that women were given these drugs an average of 14 minutes later than men were. Women on thrombolytic therapy still do better than those not given these drugs. The bottom line is that thrombolytic therapy is life-saving, and appropriate candidates, regardless of age or gender, should not be denied this therapy. Thrombolytics should be avoided or used with great caution in the following patients:
Thrombolytics should not be used in the following patients:
Other Heart Supportive DrugsAfter a heart attack, the patient may need a number of different medications, depending on their risk factors for a future heart attack:
Treatment for Patients in Shock or with Heart FailureSeverely ill patients, particularly those in cardiogenic shock (a dangerous condition that includes a drop in blood pressure and other abnormalities) or with heart failure, will be monitored closely and stabilized. Oxygen is administered, and fluids are given or replaced when it is appropriate to either increase or reduce blood pressure. Such patients may be given dopamine, dobutamine, or both. Other treatments depend on the specific condition. Heart failure. Intravenous furosemide may be administered. Patients may also be given nitrates, and ACE inhibitors, unless they have a severe drop in blood pressure or other conditions that preclude them. Clot-busting drugs or angioplasty may be appropriate and life-saving in many of these patients, although heart failure patients are less likely to be given these treatments. Cardiogenic Shock. A procedure called intra-aortic balloon counterpulsation (IABP) is proving to help these patients when used in combination with thrombolytic therapy. IABP involves inserting a catheter containing a balloon, which is inflated and deflated within the artery to boost blood pressure. Left ventricular assist devices and early angioplasty might be considered. An important study published in 2006 in the Journal of the American Medical Association indicated that early surgical intervention is important for patients who have cardiogenic shock. The study found that patients who had angioplasty or bypass surgery within 6 hours of a heart attack complicated by shock had greatly improved odds for long-term survival compared to patients who received intensive medical therapy with clot-busting drugs. Treatment of ArrhythmiasAn arrhythmia is a deviation from the heart's normal beating pattern caused when the heart muscle is deprived of oxygen and is a dangerous side effect of a heart attack. A very fast or slow rhythmic heart rate often occurs in patients who have had a heart attack, and is not usually a dangerous sign. Premature beats or very fast arrhythmias called tachycardia, however, may be predictors of ventricular fibrillation. This is a lethal rhythm abnormality, in which the ventricles of the heart beat so rapidly that they do not actually contract but quiver ineffectually. The pumping action necessary to keep blood circulating is lost. Preventing Ventricular Fibrillation. People who develop ventricular fibrillation do not always experience warning arrhythmias, and to date, there are no effective drugs for preventing arrhythmias during a heart attack.
Treating Ventricular Fibrillation.
Managing Other Arrhythmias. People with an arrhythmia called atrial fibrillation have a higher risk for stroke after a heart attack and should be treated with anticoagulants such as warfarin (Coumadin). Other rhythm disturbances called bradyarrhythmias (very slow rhythm disturbances) frequently develop in association with a heart attack and may be treated with atropine or pacemakers. [For more information on atrial fibrillation, ICDs, and pacemakers see In-Depth Report #45: Stroke.] MedicationsThrombolytic, also called clot-busting or fibrinolytic, drugs are now mainstays in the early treatment of many patients with heart attacks. These drugs dissolve the clot, or thrombus, responsible for causing artery blockage and heart-muscle tissue death. Specific ThrombolyticsThe standard thrombolytic drugs are recombinant tissue plasminogen activators or rt-PAs. They include alteplase (Activase) and reteplase (Retavase). Both are similar in effectiveness, although reteplase is easier to administer. Tenecteplase (TNKase), a newer drug, can be delivered more rapidly than alteplase, and to date, survival rates are similar. Streptokinase (Kabikinase, Streptase) is sometimes used but is somewhat less effective that the others. Thrombolytic AdministrationThe sooner that thrombolytic drugs are given after a heart attack, the better. The benefits of thrombolytics are highest within the first 3 hours. They can still help if given within 12 hours of a heart attack. A thrombolytic drug, such as alteplase or tenecteplase, is typically given by IV along with heparin, an anticoagulant drug. (Heparin, like aspirin, cannot destroy existing blood clots but can prevent clots from reforming after they are broken up.) Enoproxin, a form of heparin called low-molecular weight heparin, may be more beneficial than standard heparin. Other anticlotting drugs are being tested in combination with thrombolytic drugs for emergency treatment following a severe heart attack. Several 2005 studies have indicated that the antiplatelet drug clopidogrel (Plavix) can help prevent arteries from reclosing, and a second heart attack, when given along with aspirin and thrombolytic drugs. The studies evaluated patients who received thrombolytic drugs for treatment of STEMI (severe heart attacks with complete artery blockage). ComplicationsHemorrhagic stroke, usually occurring during the first day, is the most serious complication of thrombolytic therapy, but fortunately it is rare. Streptokinase given without heparin poses the lowest risk (although it is also less effective than other regimens in restoring blood flow). In general, the mortality rate from bleeding is only 3 in 1,000 patients treated with thrombolytics, whereas 39 patients in 1,000 would die without these clot-busting drugs. Recent evidence suggests that the survival benefits of thrombolytic therapy, particularly in combination with aspirin, last for years. Aspirin and Other Anti-Clotting DrugsAnti-clotting drugs that inhibit or break up blood clots are used at every stage of heart disease. They are generally classified as either antiplatelets or anticoagulants. All anti-clotting therapies carry the risk of bleeding, which can lead to dangerous situations, including stroke. Anti-platelet Drugs. These drugs prevent formation of blood platelets. Platelets are very small disc-shaped blood cells that are important for blood-clotting.
Anticoagulants. Anticoagulants thin blood. They include:
How Anti-Clotting Drugs Are Used For Heart Attacks. Unlike the thrombolytic (clot-busting) drugs, which are used to break up blood clots during a heart attack, anti-clotting drugs are used to prevent blood clots from forming in the first place. Such drugs are sometimes used along with thrombolytics, immediately after a heart attack, and also as on-going maintenance to prevent a heart attack.
All of these drugs pose a risk for bleeding. [For more information on these medications, see In-Depth Report #03: Coronary artery disease.] Beta-BlockersBeta-blockers reduce the oxygen demand of the heart by slowing the heart rate and lowering pressure in the arteries. They are effective for reducing deaths from heart disease. These drugs include propranolol (Inderal), carvedilol (Coreg), bisoprolol (Zebeta), acebutolol (Sectral), atenolol (Tenormin), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol-XL), and esmolol (Brevibloc). Administration During a Heart Attack. The beta-blocker metoprolol is given through an IV within the first few hours of a heart attack to reduce the destruction of heart tissue. However, a study suggests that emergency intravenous use of metoprolol may increase the risk of cardiac shock. Prevention After a Heart Attack. Beta-blockers taken by mouth are also used on a long-term basis (“maintenance therapy”) after a first heart attack to help prevent future heart attacks. Side Effects. Beta-blocker side effects include fatigue, lethargy, vivid dreams and nightmares, depression, memory loss, and dizziness. They can lower HDL (“good”) cholesterol. Beta-blockers are categorized as non-selective or selective. Non-selective beta-blockers such as carvedilol and propranolol can narrow bronchial airways. These beta-blockers should not be used by patients with asthma, emphysema, or chronic bronchitis. Patients should not abruptly stop taking these drugs. The sudden withdrawal of beta-blockers can rapidly increase heart rate and blood pressure. The doctor may want the patient to slowly decrease the dose before stopping completely. Statins and Other Cholesterol and Lipid-Lowering DrugsIn 2004, the National Cholesterol Education Program issued updated recommendations on how to control cholesterol levels. These guidelines emphasize that patients should lower their LDL (“bad”) cholesterol and recommend that more people take LDL-lowering medication. Lowering LDL cholesterol and raising HDL (“good”) cholesterol can significantly reduce the risk of heart disease. Several different types of drugs (statins, bile-acid binding resins, niacin, and fibrates) are used to treat cholesterol. [For more information, see In-Depth Report #23: Cholesterol.] Statins are the most important of these drugs. Brands include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). A major analysis of over 200 studies found that statins reduced the risk for heart problems by 60% and stroke by 17%. A 2005 review found that the more that statins lower LDL, the more they reduce CAD and other heart disease risks. An important 2006 study found that aggressive treatment with statins may have the potential to reverse coronary artery disease. In the study, rosuvastatin reduced fatty plaque in the arteries in addition to improving LDL and HDL cholesterol levels. However, a follow-up 2007 study of rosuvastatin indicated that while the drug slowed the rate of atherosclerotic progression, it did not reverse heart disease. Future studies will continue to investigate this issue. A 2006 review of studies indicated that early, intensive therapy with statins can help reduce the risk of death, unstable angina, and revascularization (surgery to restore blood flow) for patients with acute coronary syndrome. The review indicated that statins work best when they are prescribed within 14 days of hospitalization for acute coronary syndrome. The researchers found that the effect of statins began about 4 months after starting drug therapy and that benefits lasted up to 2 years. Side effects of statins may include stomach upset, headaches, skin rashes, muscle aches, sexual dysfunction, drowsiness, dizziness, nausea, constipation, and peripheral neuropathy (numbness or tingling in the hands and feet). The main safety concern with statins is an uncommon condition called myopathy, which can cause muscle and joint pain and possible muscle damage. Doctors will immediately stop statin therapy if myopathy occurs. Patients should talk to their doctor about any unusual muscle discomfort or weakness or if their urine becomes brown-colored. Statins can also affect the liver, particularly at higher doses, so patients taking these drugs should receive regular liver function tests. Angiotensin Converting Enzyme InhibitorsAngiotensin converting enzyme (ACE) inhibitors are important drugs for treating patients who have had a heart attack, particularly for patients at risk for heart failure. These drugs are commonly used to treat hypertension and are recommended as first-line treatment for people with diabetes and kidney damage. ACE inhibitors include captopril (Capoten), ramipril (Altace), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), perindopril (Aceon), and lisinopril (Prinivil, Zestril). Side Effects. Side effects of ACE inhibitors are uncommon but may include an irritating cough, excessive drops in blood pressure, and allergic reactions. In the past, doctors sometimes avoided giving aspirin to patients who were taking ACE inhibitors because the combination was believed to cause kidney problems. But, a 2005 study of patients with both coronary artery disease and heart failure found that taking aspirin and ACE inhibitor together is safe. MagnesiumMagnesium has blood-thinning properties and may help open blood vessels. It is important to correct any magnesium deficiencies in patients (such as those who are taking diuretics). Infection-Fighting MedicationsFlu Shots. Influenza vaccinations may help protect patients against another heart attack during flu season. Antibiotics. Researchers have investigated antibiotics for treating patients with heart disease and past infection of the bacteria Chlamydia pneumoniae. Results from several large-scale clinical trials, published in 2003 in the Journal of the American Medical Association (JAMA) and presented in 2004 at the European Society of Cardiology annual meeting, suggest that antibiotic treatment provides no benefit in preventing heart attack or other cardiac events in patients with coronary artery disease. While it is still possible that C. pneumoniae may play a role in triggering inflammatory responses associated with ACS, antibiotic therapy is no longer considered appropriate for treatment or prevention of heart disease. Investigational DrugsStem Cell Therapy. Researchers are investigating whether infusions of adult stem cells can help improve outcomes in patients who have a heart attack. Results from three small trials, published in 2006 in the New England Journal of Medicine, suggested that stem cell therapy may have some benefits in improving heart function. None of the studies reported treatment complications. Research presented at the 2007 American College of Cardiology annual meeting discussed intravenous stem cell therapy with Provacel (a commercial stem cell preparation). In the small study, patients who received Provacel had fewer adverse events (such as arrhythmia) and improved heart, lung, and overall function compared to patients who received placebo. Patients in the study received a Provacel infusion within 10 days of having a heart attack. SurgeryPercutaneous coronary intervention (PCI), also called angioplasty, and coronary artery bypass graft surgery are the standard operations for opening narrowed or blocked arteries. They are known as revascularization procedures.
 Click the icon to see an illustrated series detailing a heart bypass surgery. Angioplasty (PCI) and Coronary StentsPercutaneous coronary intervention (PCI), also called angioplasty, involves procedures such as percutaneous transluminal coronary angioplasty (PTCA) that help open the blocked artery. A typical angioplasty procedure involves the following steps:  Click the icon to see an image of an angioplasty.
Experts recommend that appropriate patients receive angioplasty and stenting within 90 minutes after having a heart attack and no later than 12 hours following an attack. Although some hospitals have been performing angioplasty and stenting for up to a month following a heart attack, a landmark 2006 study found that delayed surgical intervention is not helpful for most patients. The Occluded Artery Trial (OAT), published in the New England Journal of Medicine, reported that balloon angioplasty and stenting failed to prevent heart complications in patients who received the procedure 3 – 28 days after a heart attack. The trial compared angioplasty to medications (aspirin, ACE inhibitors, beta-blockers, statins, clopidogrel). Experts are now recommending delayed angioplasty and stenting only for patients who are unstable or who continue to have chest pain following a heart attack. This procedure may also be appropriate for patients who cannot tolerate beta-blocker drugs, which are commonly prescribed to help improve survival after a heart attack. Complications occur in about 10% of patients (about 80% within the first day). Serious side effects include heart attack and the need for additional surgery. Best results occur in hospital settings with experienced teams and backup. Women who have angioplasty after a heart attack have a higher risk of death than men. Reclosure and Blockage During or Shortly after Angioplasty. Reclosure of the artery often occurs during or shortly after angioplasty. A number of anticlotting drugs are used to reduce this risk. Clopidogrel (Plavix) is often given along with aspirin and thrombolytic drugs (such as abciximab) in the days before angioplasty surgery, to help prevent heart attack or stroke following surgery. Research suggests that abciximab (ReoPro) is especially helpful for patients with acute coronary syndrome. Prevention of Restenosis. Narrowing or reclosing of the artery (restenosis) occurs within a year of angioplasty in many angioplasty patients, often requiring a repeat operation. In restenosis, the narrowing of the artery is usually due to scarring, not blood clots. Drug-eluting stents, which are coated with sirolimus (Rapamune) or paclitaxel (Taxol), can help prevent restenosis. Several 2006 studies indicated that this type of stent may be better than a bare metal stent for patients who have experienced a STEMI heart attack. However, because drug-eluting stents reduce arterial tissue growth, they can increase the risks of blood clots. In February 2007, the American Heart Association and other professional organization issued an extremely important joint advisory statement. The statement advises that all patients who have drug-eluting stents must continue to take aspirin and clopidogrel (or, rarely,) ticlopidine for at least 1 year after the stent is inserted to reduce the risk of blood clots. Clopidogrel and ticlopidine are thienopyridine drugs that, like aspirin, help prevent blood platelets from clumping together. It is very important that patients who have drug-eluting stents take both aspirin and a thienopyridine drug. If for some reason patients cannot take a thienopyridine drug, they should receive a bare metal stent instead of a drug-eluting stent. [For more information, see In-Depth Report #03: Coronary artery disease.]  Click the icon to see an illustrated series detailing balloon angioplasty. Coronary Artery Bypass Graft Surgery (CABG)Coronary artery bypass graft surgery (CABG) is the alternative elective procedure to angioplasty for opening blocked arteries in patients with severe angina, particularly those who have two or more blocked arteries. It is a very invasive procedure, however:
Mortality rates with this procedure after a heart attack are much higher (6%) than when it is used electively (1 - 2%). How or when it should be used after a heart attack, then, is controversial. A 2002 study attempted to determine which patients are at highest risk for poor results from CABG after a heart attack. The study found higher risks for women, patients over age 75, and those with heart failure or other severe heart problems. RehabilitationLifestyle measures, particularly dietary factors, are equally important in preventing heart attacks and must be strenuously adhered to. Physical Activity and RehabilitationPhysical rehabilitation is extremely important after a heart attack. It has been associated with a 25% reduction in mortality rates at 3 years. Rehabilitation may include:
Patients generally return to work in about 2 months, although timing can vary depending on the severity of the condition. Sexual activity after a heart attack carries a very low risk and is believed to be safe, particularly in people who had exercised regularly before the attack. In any case, the feelings of intimacy and love that accompany healthy sex can help offset depression, a far greater risk for a future attack. Emotional RehabilitationMajor depression affects between 15 - 23% of patients with ACS or heart attacks. Many studies suggest that depression is a major predictor for increased mortality in both women and men. (One reason may be that depressed patients are less likely to comply with their heart medications.) Psychotherapeutic techniques, especially cognitive behavioral therapies, are very helpful. Doctors have been reluctant to prescribe antidepressant drugs after ACS or a heart attack because older antidepressants tended to have adverse effects on the heart. Newer antidepressants may be safer. Studies on sertraline (Zoloft), one of the selective serotonin reuptake inhibitor (SSRI) antidepressants, have not reported harmful effects for patients who have had a heart attack. It is not yet clear if other SSRIs are equally safe and effective. Resources
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Review Date:
4/16/2007 Reviewed By: Harvey Simon, M.D., Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-
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