HEART ATTACK AND ACUTE CORONARY SYNDROME
Symptoms of a Heart AttackCommon signs and symptoms of a heart attack include:
- Chest pain or discomfort (angina), which can feel like pressure, squeezing, fullness, or pain in the center of the chest. With a heart attack, the pain usually lasts for more than a few minutes, but it may increase and decrease in intensity.
- Discomfort in the upper body including arms, neck, back, jaw, or stomach.
- Shortness of breath.
- Nausea and vomiting.
- Breaking out in cold sweat.
- Dizziness or fainting.
- Women are less likely to have chest pain.
Immediate Treatment of a Heart AttackThe American Heart Association and the American College of Cardiology recommend:
- If you think you are having a heart attack, call 03 right away. After you call 03, chew a tablet of aspirin. Be sure to tell the medical assistant about it so an additional aspirin dose is not given.
- Angioplasty, also called percutaneous coronary intervention (PCI), is a procedure that should be performed within 90 minutes of a heart attack. Patients suffering a heart attack should be transported to hospitals equipped to perform PCI.
- Fibrinolytic therapy should be given within 30 minutes of a heart attack if a center that performs PCI is not available. The patient should then be transferred to a PCI facility without delay
Secondary Prevention of a Heart AttackSecondary prevention measures are essential to help prevent another heart attack. Before leaving the hospital discuss with your doctor:
- High blood pressure and cholesterol control (on discharge from the hospital statins, ACE inhibitors, and beta blockers are prescribed).
- Aspirin and the anti-platelet drug clopidogrel (Plavix), which most patients will need to take on an ongoing basis. Prasugrel (Effient) is a new antiplatelet drug that may be used as an alternative to clopidogrel.
- Cardiac rehabilitation and regular exercise program.
- Weight management.
- Smoking cessation.
IntroductionThe heart is a complex organ of the human’s body. Throughout the life, it keeps pumping blood, thus providing all body tissues with oxygen and essential nutrients via the arterial system. To perform this intensive task, the heart muscle itself needs the sufficient amount of the oxygen-rich blood which is supplied to it through the network of coronary arteries. These arteries carry the oxygen-rich blood to the wall of the heart muscle (myocardium).
A heart attack (myocardial infarction) occurs when blood flow to the heart muscle is blocked, and tissue death occurs from loss of oxygen, severely damaging a portion of the heart.
Ischemic heart disease causes heart attacks. Ischemic heart disease is an eventual result of atherosclerosis which causes blockage of arteries (ischemia) and prevents oxygen-rich blood from reaching the heart.
A Heart AttackA heart attack (myocardial infarction) is among the most serious outcome of atherosclerosis. It can occur as a result of one of two effects of atherosclerosis:
- If the atheromatous plaque 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 blood clot completely blocks the passage of oxygen-rich blood to the heart.
- If the artery becomes completely blocked after gradual buildup of atheromatous plaque due to atherosclerosis. Heart attack may occur if not enough oxygen-rich blood can flow past the blockage.
AnginaAngina, the primary symptom of coronary artery disease, is typically experienced as chest pain. There are two kinds of angina:
- Stable angina This is predictable chest pain that can usually be managed with lifestyle changes and medications, such as low-dose aspirin and nitrates.
- Unstable angina This situation is much more serious than stable angina, and is often an intermediate stage between stable angina and a heart attack. Unstable angina is part of a condition called acute coronary syndrome.
Acute coronary syndromeAcute coronary syndrome (ACS) is a severe and sudden heart condition that, although needing intensive treatment, has not developed into a full blown heart attack. Acute coronary syndrome includes:
- Unstable angina Unstable angina is potentially serious and chest pain is persistent, but blood tests do not show markers for a heart attack.
- • Non ST-segment Elevation Myocardial Infarction (non Q-wave myocardial infarction). It is diagnosed when blood tests and ECG indicate a heart attack that does not involve the full thickness of the heart muscle. The injury in the arteries is less severe than with a full-blown heart attack.
Risk FactorsThe risk factors for a heart attack are the same as those for ischemic heart disease. They include:
Agehe risks for ischemic heart disease increase with age. About 85% of people who die from cardiovascular diseases are over the age of 65. For men, the average age of a first heart attack is 66 years.
GenderMen have a greater risk for ischemic heart disease and are more likely to have heart attacks earlier in life than women. Women’s risk for cardiovascular diseases increases after menopause, and they are more likely to have angina than men.
Genetic Factors and Family HistoryCertain genetic factors increase the likelihood of developing risk factors, such as diabetes, elevated cholesterol and high blood pressure.
Race and EthnicityAfrican-Americans have the highest risk of cardiovascular diseases in part due to their high rates of severe high blood pressure as well as diabetes and obesity.
Medical ConditionsObesity and Metabolic Syndrome. Excess body fat, especially around the waist, can increase the risk for cardiovascular diseases. Obesity also increases the risk for high blood pressure and diabetes that are associated with cardiovascular diseases. Obesity is particularly hazardous when it is a part of the metabolic syndrome, a pre-diabetic condition that is significantly associated with cardiovascular diseases. This syndrome is diagnosed when three of the following conditions are present:
- Abdominal obesity
- Low HDL cholesterol
- High triglyceride levels
- High blood pressure
- Insulin resistance (diabetes or pre-diabetes)
High blood pressure High blood pressure (hypertension) is associated with ischemic heart disease and heart attack. For an adult, a normal blood pressure reading is below 120/80 mm Hg. 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.
Diabetes. Diabetes, especially for people whose blood sugar levels are not well controlled, significantly increases the risk of developing cardiovascular diseases. In fact, cardiovascular diseases and strokes are the leading causes of death in people with diabetes. People with diabetes are also at risk for arterial hypertension and hypercholesterolemia, blood clotting problems, kidney diseases, and impaired nerve function, all of which can damage the heart.
Lifestyle FactorsPhysical Inactivity. Exercises have a number of effects that benefit the heart and circulation, including improving cholesterol levels and blood pressure and maintaining weight control. People living sedentary lifestyle are almost twice as likely to suffer heart attacks as are people who exercise regularly.
Smoking. Smoking is the most important risk factor for cardiovascular disease. Smoking can cause elevated blood pressure, worsen lipids, and make platelets very sticky, raising the risk of clottage. Although heavy cigarette smokers are at the greatest risk, 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 smoking also increases the risk of cardiovascular diseases in nonsmokers.
Alcohol. Moderate alcohol consumption (one glass of red dry wine a day) can help boost HDL ‘good’ cholesterol level. Alcohol may also prevent blood clots and inflammation. By contrast, heavy drinking harms the heart. In fact, cardiovascular diseases are the leading cause of death in alcoholics.
Diet. Diet can play an important role in protecting the heart, especially by reducing dietary sources of trans fats, saturated fats, and cholesterol and restricting salt intake that contributes to high blood pressure.
NSAIDs and COX-2 InhibitorsAll non-steroidal anti-inflammatory drugs (NSAIDs) - except 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.
NSAIDs include nonprescription drugs like ibuprofen (Advil, Motrin) and prescription drugs like diclofenac (Cataflam, Voltaren). Celecoxib (Celebrex), currently the only COX-2 inhibitor available in the U.S., has been linked to cardiovascular risks, such as a heart attack and stroke. Patients who have had heart attacks should talk to their doctors before taking any of these drugs.
The American Heart Association recommends that patients who have, or who are at risk for, cardiovascular diseases first try non-drug methods of pain relief (such as 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 effective and safe dose of acetaminophen (Tylenol) or aspirin before using an NSAID. The COX-2 inhibitor celecoxib (Celebrex) should be a last resort.
PrognosisHeart attacks may be rapidly fatal, evolve into a chronic disabling condition, or lead to full recovery. The long-term prognosis for both duration and quality of life after a heart attack depends on its severity, the amount of damage sustained by the heart muscle, and the preventive measures taken afterward.
Patients who have had a heart attack have a higher risk of a second heart attack. Although no tests can absolutely predict whether another heart attack occurs, patients can avoid having another heart attack by living a healthy lifestyle 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.
A heart attack also increases the risk for other heart problems, including abnormal heart rhythms, heart valve damage, and stroke.
Higher Risk Individuals. A heart attack is always more serious in certain people, including:
- People with a history of heart disease or multiple risk factors for cardiovascular diseases
- People with heart failure
- People with diabetes
- People on long-term dialysis
- Women are more likely to die from a heart attack than men. The risk of death is the highest in younger women.
The presence of the following conditions during a heart attack can contribute to a poorer prognosis:
- Arrhythmias (disturbed heart rhythms). A dangerous arrhythmia called ventricular fibrillation is a major cause of early death from heart attack. Arrhythmias are more likely to occur within the first 4 hours of a heart attack, and they are associated with a high mortality rate. Patients who are successfully treated, however, have the same long-term prognosis as those who do not have such arrhythmias.
- Cardiogenic shock. This very dangerous condition is associated with very low blood pressure, reduced urine levels, and metabolic disorders. Shock occurs in 7% of heart attacks.
- Heart block, also called atrio-ventricular (AV) block, is a condition in which the electric conduction of nerve impulses to muscles in the heart is slowed or interrupted. Although heart block is dangerous, it can be treated effectively with a pacemaker, and it rarely causes any long-term complications in patients who survive it.
- Heart failure. The damaged heart muscle is unable to pump all the blood that the tissues need. Patients experience fatigue, shortness of breath, and fluid build-up.
SymptomsHeart attack symptoms can vary. They may appear suddenly and severely or may progress slowly, beginning with mild pain. Symptoms can also vary between men and women. Women are less likely to have classic chest pain than men, but they are more likely to experience shortness of breath, nausea or vomiting, or jaw and back pain.
Common signs and symptoms of a heart attack include:
- Chest pain. Chest pain or discomfort (angina) is the main sign of a heart attack. It can feel like pressure, squeezing, fullness, or pain in the center of the chest. Patients with disease of coronary arteries who have stable angina often experience chest pain that lasts for a few minutes and then goes away. With heart attack, the pain usually lasts for more than a few minutes and the feeling may go away but then come back.
- Discomfort in the upper body. People having a heart attack may feel discomfort in the arms, neck, back, jaw, or stomach.
- Shortness of breath can occur with or without chest pain.
- Nausea and vomiting.
- Breaking out in cold sweat.
- Dizziness or fainting.
- Sharp pain brought on by breathing in or when coughing
- Pain that is mainly or only in the middle or lower abdomen
- Pain that can be pinpointed with the tip of one finger
- Pain that can be reproduced by moving or pressing on the chest wall or arms
- Pain that is constant and lasts for hours (although no one should wait hours if they suspect they are having a heart attack)
- Pain that is very brief and lasts for a few seconds
- Pain that spreads to the legs
- However, the presence of these symptoms does not always rule out a serious heart event.
Silent IschemiaSome people with severe coronary artery lesion do not have angina. This condition is known as silent ischemia. This is a dangerous condition because patients have no warning signs of a heart disease. Some studies suggest that people with silent ischemia experience higher complication and mortality rates than those with angina pain.
What to Do When Symptoms OccurPeople who have symptoms of a heart attack should take the following actions:
- For angina patients, take one nitroglycerin dose either as an under-the-tongue tablet or in spray form at the onset of symptoms. Take another dose every 5 minutes up to three doses or when the pain is relieved, whichever comes first.
- Call 03 or the local emergency number. This should be the first action taken if angina patients continue to experience chest pain after taking the full three doses of nitroglycerin. However, only 20% of heart attacks occur in patients with previously diagnosed angina. Therefore, anyone who develops heart attack symptoms should contact emergency services.
- The patient should chew and swallow aspirin (250-500 mg) and be sure to tell emergency health providers so an additional dose is not given.
- Patients with chest pain should go immediately to the nearest emergency room, preferably traveling by ambulance. They should not drive themselves.
DiagnosticsWhen 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:
- The patient will report all symptoms so that a health care provider can rule out either a non-heart problem or possible other serious accompanying conditions.
- The patient will report all symptoms so that a health care provider can rule out either a non-heart problem or possible other serious accompanying conditions.
- Blood tests showing elevated levels of certain factors (troponins and creatinphosphokinase-MB) indicate heart damage. (However, a doctor will not wait for results, before administering treatment if a heart attack is strongly suspected.)
- Imaging tests, including echocardiogram and perfusion scintigraphy, help rule out a heart attack if there is any question.
Electrocardiogram (ECG)An electrocardiogram (ECG) measures and records the cardiac electrical activity. The waves measured by the ECG correspond to the contraction and relaxation pattern of different parts of the heart. Specific waves seen on an ECG are named with letters:
- P. The P wave is associated with the contractions of the atria (the two chambers in the heart that receive blood from outside).
- QRS. The QRS is a series of waves associated with ventricular contractions. (The ventricles are the two major pumping chambers in the heart.)
- T and U. These waves follow the ventricular contractions.
The most important wave patterns in diagnosing and determining treatment for a heart attack are called ST elevations and Q waves.
Elevated ST Segments: A heart Attack. An elevated ST segment is a strong indicator of a heart attack. It indicates that an artery to the heart is blocked and that the full thickness of the heart muscle is damaged. A Q-wave myocardial infarction (ST-segment elevation myocardial infarction) is developed.
However, the ST segment elevation does not always mean that the patient has a heart attack. A heart sac inflammation (pericarditis) is another cause of the ST-segment elevation.
With non-elevated ST Segment angina and acute coronary syndrome develop.
A depressed or horizontal ST wave suggests some blockage and the presence of cardiovascular diseases, 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:
- Stable Angina (blood test results or other tests show no serious problems and chest pain resolves). Between 25 - 50% of people who have angina or silent ischemia have normal ECG readings.
- Acute Coronary Syndrome (ACS). This includes severe and sudden heart conditions that require aggressive treatment but have not developed into a full-blown heart attack. ACS refers to either unstable angina or non ST-segment elevation myocardial infarction, also referred to as non Q-wave myocardial infarction. Unstable angina is potentially serious, and chest pain is persistent, but blood tests do not show markers for heart attack. With non Q-wave myocardial infarction, the blood tests indicate a heart attack, but in most cases, injury to the heart is less serious than with a full-blown heart attack.
Echocardiogram (ECHOCG)An echocardiogram is a noninvasive test that uses ultrasound images of the heart. Your doctor can see whether a part of your heart muscle has been damaged and is not moving. An echocardiogram may also be used as part of an exercise stress test, to detect the location and extent of heart muscle damage at the time of a heart attack or soon after you leave the hospital.
Radionuclide Methods (Thallium Stress Test)Radionuclide procedures help visualize the passage of radioactive tracers through the region of the heart. Such tracing elements are typically given intravenously. This technique is useful for diagnosing and determining:
- Severity of unstable angina when less expensive diagnostic approaches are ineffective
- Severity of chronic ischemic heart disease
- Success of surgeries for ischemic heart disease
- Whether a heart attack has occurred
- The location and extent of heart muscle damage at the time of a heart attack or soon after you leave the hospital.
AngiographyAngiography is an invasive test. It is used for patients who show strong evidence for angina on stress and other tests and for patients with acute coronary syndrome. In the procedure:
- A narrow tube (catheter) is inserted into an artery, usually in the arm or leg, and then threaded up through the body to the coronary arteries.
- A dye is injected via the catheter into the coronary arteries, and an x-ray record is performed.
- As a result, a map of the coronary circulation is obtained, revealing any blocked areas.
Biologic MarkersWhen heart cells are damaged, they release different enzymes and other molecules into the bloodstream. 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. Tests for these markers are often performed in the emergency room or hospital when a heart attack is suspected. Some markers include:
- Troponins. The proteins of cardiac troponin T and I are released when the heart muscle is damaged. Both are proving to be among the best diagnostic indications of heart attacks. They can help diagnose heart attack and identify patients with ACS who might otherwise be misdiagnosed.
- Creatine kinase myocardial band (creatinphosphokinase-MB). Creatinphosphokinase-MB has been a standard marker, but it is less sensitive than troponin. The elevated creatinphosphokinase-MB levels can appear in people without heart pathology.
TreatmentTreatment options for a heart attack, and acute coronary syndrome, include:
- Oxygen therapy
- Relieving pain and discomfort using nitroglycerin or morphine
- Controlling any arrhythmias (abnormal heart rhythms)
- Blocking further clotting (if possible), using aspirin or clopidogrel (Plavix), as well as a anticoagulants such as heparin
- Opening up the artery that is blocked as soon as possible, by performing angioplasty or using medicines that open up the clot.
- Giving the patient beta blockers, calcium channel blockers, or ACE inhibitor drugs to help the heart muscle and arteries work better
Immediate Supportive TreatmentsThese are similar for patients with both ACS and a heart attack.
Oxygen. Oxygen is usually administered through a tube that enters through the nose or a mask.
Aspirin. The patient is given aspirin if one was not taken at home.
Medications for Relieving Symptoms:
- Nitroglycerin. Most patients will receive nitroglycerin during and after a heart attack, usually under the tongue. Nitroglycerin decreases blood pressure and opens the blood vessels around the heart, increasing blood flow. Nitroglycerin may be given intravenously in certain cases (recurrent angina, heart failure, or high blood pressure).
- Morphine. Morphine not only relieves pain and reduces anxiety but also opens blood vessels, aiding the circulation of blood and oxygen to the heart. Morphine can decrease blood pressure and slow down the heart. Other drugs may be used, as well.
Opening the Arteries: Emergency Angioplasty or Thrombolytic DrugsWith a heart attack, clots form in the coronary arteries that block the blood flow. Opening a clotted artery as quickly as possible is the best approach to improve survival and limit the amount of heart muscle that is permanently damaged. Heart attack patients should be directed to appropriate medical centers as quickly as possible.
The standard medical and surgical solutions for opening arteries are:
- Angioplasty, also called percutaneous coronary intervention (PCI), is the preferred emergency procedure for opening the arteries. Angioplasty should be performed promptly for patients with a heart attack, preferably within 90 minutes of arriving at a hospital. In most cases, a stent is placed in the artery to form an inner frame and improve the blood flow.
- Thrombolytics, the clot-busting drugs, are the standard medications used to open the arteries. A thrombolytic therapy should be performed within 3 hours after the onset of symptoms. Patients who arrive at a hospital that is not equipped to perform PCI should receive clot-busting therapy and then be transferred to a PCI center without delay.
- Coronary artery bypass surgery (CABG) is sometimes used as an alternative to angioplasty.
ThrombolyticsThrombolytic, or fibrinolytic drugs are recommended as alternatives to angioplasty. These drugs dissolve the clot, or thrombus, responsible for causing artery blockage and heart-muscle tissue death.
Generally speaking, thrombolysis is considered a good option for patients with myocardial infarction within the first 3 hours. Ideally, these drugs should be given within 30 minutes after arrival at the hospital if angioplasty is not a viable option. Other situations when a clot-busting drug may be used include:
- Necessity for prolonged transportation
- PCI will be performed after a long period of time
- PCI procedure was not successful
- Patients older than 75 years
- When symptoms remain for more than 12 hours
- Pregnant women
- People who have experienced recent trauma (especially head injury) or invasive surgery
- People with active peptic ulcer
- Patients who have been given a prolonged cardiopulmonary resuscitation
- Current users of anticoagulants
- Patients who have experienced any recent major bleeding
- Patients who have suffered a stroke
- Patients with uncontrolled high blood pressure, especially when systolic is higher than 180 mm Hg
Thrombolytic Administration. The sooner the 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.
Complications. Hemorrhagic stroke, usually occurring during the first day, is the most serious complication of thrombolytic therapy, but fortunately it is rare.
Revascularization Procedures: Angioplasty and Bypass SurgeryPercutaneous coronary intervention (PCI), also called angioplasty, and coronary artery bypass surgery are the standard operations for opening narrowed or blocked arteries. They are known as revascularization procedures.
- Emergency angioplasty/PCI is the standard procedure for heart attacks and should be performed preferably within 90 minutes of a heart attack. Studies have shown that balloon angioplasty and stent placement surgery fail to prevent heart complications in patients who receive the procedure 3 - 28 days after a heart attack.
- Coronary artery bypass surgery is typically used as elective surgery for patients with blocked arteries. Sometimes it may be used after a heart attack if angioplasty or thrombolytics fail. Usually, it is not performed for several days to allow recovery of the heart muscles. Most patients meet the criteria for either thrombolytic drugs or angioplasty (although not all the centers are equipped to do this procedure).
- A narrow catheter (a tube) is inserted into the blocked coronary artery.
- The blocked vessel is opened using balloon angioplasty, in which a tiny balloon is inflated.
- After the balloon is deflated the lumen of the vessel is widened.
- To keep the artery open afterwards, a device called a coronary stent is used. It is an expandable metal mesh tube that is implanted during angioplasty at the site of the blockage. The stent may be bare metal or it may be coated with a special drug that slowly releases medication.
- The stent pushes against the wall of the artery to keep it open.
Drug-eluting stents, which are coated with sirolimus or paclitaxel, may help prevent restenosis. They may be better than bare metal stents for patients who have experienced a heart attack, but they can also increase the risks of blood clots.
It is very important for patients who have drug-eluting stents to take aspirin and clopidogrel (Plavix) for at least 1 year after the stent placement surgery, to reduce the risk of blood clots. Clopidogrel, like aspirin, helps to prevent blood platelets from clumping together. If patients cannot take clopidogrel along with aspirin after angioplasty and stent placement surgery for some reason, they should receive bare metal stents instead of drug-eluting stents. Prasugrel is a newer drug that may be used as an alternative to clopidogrel.
Coronary Artery Bypass Surgery (CABG). It is the alternative procedure to angioplasty, for patients who have a severe angina, particularly, for those who have two or more blocked arteries. It is a very invasive procedure, however:
- The chest is opened, and the blood is rerouted through a lung-heart machine.
- The heart is stopped during the main stage of procedure.
- Segments of veins or arteries taken from the leg, arm or chest are fashioned into grafts, which are used to reroute the blood. The blood vessel grafts are placed in front of and beyond the blocked arteries, so the blood flows through the new vessels around the blockage.
Treatment for Patients in Shock or with Heart FailureSeverely ill patients or those with heart failure, or who are in cardiogenic shock (a dangerous condition that includes a drop in blood pressure and other abnormalities), will be monitored closely and stabilized. Oxygen is administered, and fluids are given to control blood pressure. Dopamine, dobutamine, or other treatments are used.
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. Clot-busting drugs or angioplasty may be appropriate.
Cardiogenic shock. A procedure called intra-aortic balloon counterpulsation (IABP) can help patients with cardiogenic shock 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.Angioplasty might also be considered.
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 rhythms (tachycardia) may be predictors of ventricular fibrillation. This is a life-threatening arrhythmia, 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 prevention of arrhythmias during a heart attack.
- Potassium and magnesium levels should be monitored and maintained.
- Intravenous beta blockers followed by oral administration of the drugs may help prevent arrhythmias in certain patients.
- Defibrillators. Patients who develop ventricular arrhythmias are given electrical shocks with defibrillators to restore normal rhythms. Some studies suggest that implantable cardioverter-defibrillators (ICDs) may prevent further arrhythmias in heart attack survivors who are at risk for further arrhythmias.
- Antiarrhythmic Drugs. Antiarrhythmic drugs include lidocaine, procainamide, or amiodarone. Amiodarone or another antiarrhythmic drug may be used afterward to prevent future events.
MedicationsАспирин и другие дезагреганты Aspirin and other anti-clotting drugs. Anti-clotting drugs are used at every stage of heart disease. They are generally classified as either anti-platelets or anticoagulants. They are used along with thrombolytics, and also as on-going maintenance to prevent a heart attack. The anti-clotting therapy carries the risk of bleeding and stroke.
Anti-Platelet Drugs. These drugs inhibit blood platelets from sticking together, and therefore help to prevent clottage. Platelets are very small disc-shaped blood cells that are important for blood clotting.
- Aspirin. Aspirin is an anti-platelet drug. An aspirin should be taken immediately after a heart attack begins. It can be either swallowed or chewed, but chewing provides more rapid benefit. If the patient has not taken an aspirin at home, it will be given at the hospital. It is then continued daily. Using aspirin for heart attack patients reduces mortality. It is the most common anti-clotting drug, and most people with cardiovascular diseases are advised to take it daily in low dose on an ongoing basis.
- Clopidogrel (Plavix), a thienopyridine, is another type of anti-platelet drug. Clopidogrel is started either immediately or right after PCI is performed. It is used in patients experiencing heart attacks and also after thrombolytic therapy. Patients who receive a drug-eluting stent should take clopidogrel along with aspirin for at least 1 year to reduce the risk of clottage. Patients admitted for unstable angina need to take clopidogrel in case they cannot take aspirin. Clopidogrel should be also given to the patients with unstable angina who are scheduled to undergo invasive procedures. Even when patients receive medical treatment, they should continue clopidogrel for a year. Some patients may need to take clopidogrel on an ongoing basis. Prasugrel is a newer thienopyridine that may be used instead of clopidogrel in patients with acute coronary syndrome (ACS). It should not be used by patients who have a history of stroke or transient ischemic attack.
- Glycoprotein IIb/IIIa Inhibitors. These powerful anti-platelet drugs include abciximab (ReoPro) and tirofiban (Aggrastat). They are administered intravenously in the hospital and are used with angioplasty and stent placement surgery.
- Heparin is usually prescribed during the treatment with thrombolytics for at least 2 days.
- Other intravenous anticoagulants include bivalirudin (Angiomax), fondaparinux (Arixtra), and enoxaparin (Lovenox).
- Warfarin (Coumadin).
Beta blockers reduce the oxygen demand of the heart by slowing the heart rate and lowering blood pressure. They are effective for reducing deaths from cardiovascular diseases. Beta blockers are often given to patients early in their hospitalization, sometimes intravenously. Patients with heart failure or who are at risk of going into cardiogenic shock should not receive intravenous beta blockers. Long-term oral beta blocker therapy for patients with symptomatic ischemic heart disease, particularly after heart attacks, is recommended in most cases.
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 may be given within the first few hours of a heart attack to reduce damage to the heart muscle.
Prevention after a heart attack. Beta blockers taken by mouth are also used on a long-term basis (as maintenance therapy) after a first heart attack to help prevent future heart attacks.
Side Effects of beta blockers 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, thus leading to bronchospasm. Patients with bronchial asthma, emphysema, or chronic bronchitis, should not take non-selective beta blockers.
Patients should not abruptly stop taking these drugs. The sudden withdrawal of beta blockers can rapidly increase heart rate and blood pressure. It is recommended to slowly decrease the dose before stopping completely.
Statins and Other Hypoglycemic Medicines, Reducing the Level of Cholesterol
After being admitted to the hospital for acute coronary syndrome or a heart attack, patients should not discontinue statins or other medicines in case of elevated LDL ("bad") cholesterol level. Some doctors recommend that LDL should be below 70 mg/dL.
Angiotensin Converting Enzyme Inhibitors
Angiotensin-converting enzyme inhibitors (ACE inhibitors) are important drugs for treating patients who have had a heart attack, particularly for patients at risk for heart failure. ACE inhibitors should be given on the first day to all patients with a heart attack, unless there are medical reasons for not taking them. Patients admitted for unstable angina or acute coronary syndrome should receive ACE inhibitors if they have symptoms of heart failure or evidence of reduced left ventricular fraction echocardiogram. These drugs are also commonly used to treat high blood pressure (hypertension) and are recommended as first-line treatment for people with diabetes and kidney damage.
ACE inhibitors include captopril (Capoten), ramipril, enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), perindopril (Aceon), and lisinopril (Prinivil).
Side Effects. Side effects of ACE inhibitors are uncommon but may include an irritating cough, excessive drops in blood pressure, and allergic reactions.
Calcium Channel Blockers
Calcium channel blockers may provide relief in patients with unstable angina whose symptoms do not respond to nitrates and beta blockers, or for patients who are unable to take beta blockers.
Secondary PreventionPatients can reduce the risk for a second heart attack by following secondary prevention measures explained on discharge from the hospital. Lifestyle choices, particularly dietary factors, are equally important in preventing heart attacks and must be strenuously adhered to.
Blood pressure. Aim for a blood pressure of less than 130/80 mm Hg.
Cholesterol. LDL (“bad”) cholesterol should be substantially less than 100 mg/dL. All patients who have had a heart attack should receive a prescription for a statin drug before being discharged from the hospital. It is also important to control dietary cholesterol by reducing intake of saturated fats to less than 7% of total calories. Increased omega-3 fatty acid consumption can help reduce triglyceride levels.
Exercise. Exercise for 30 - 60 minutes 7 days a week (or at least a minimum of 5 days a week).
Weight Management. Combine exercise with a healthy diet rich in fresh fruits, vegetables and low-fat dairy products. Your body mass index (BMI) should be 18.5 - 24.8. Waist circumference is also an important measure of heart attack risk. Men’s waist circumferences should be less than 40 inches (102 centimeters), while women’s should be below 35 inches (89 centimeters).
Smoking. It is essential to stop smoking. Also, avoid exposure to second-hand smoke.
Anti-Platelet Drugs. Your doctor may recommend you take aspirin (75 - 81 mg) on a daily basis. If you have had a drug-coated stent inserted, you must take clopidogrel (Plavix) or prasugrel (Effient) along with aspirin for at least 1 year following surgery. (Aspirin is also recommended for some patients as primary prevention of a heart attack.)
Other Drugs. Your doctor may recommend you to take an ACE inhibitor or beta blocker drug on an ongoing basis. It is also important to have an annual influenza (“flu”) vaccination.
Rehabilitation. Physical RehabilitationPhysical rehabilitation is extremely important after a heart attack. Cardiac rehabilitation may include:
- Walking. The patient usually sits in a chair on the second day, and begins to walk on the second or third day.
- Most patients undergo low-level exercise tolerance tests early in their recovery.
- After 8 - 12 weeks, many patients, even those with heart failure, benefit from supervised exercise programs. Recommendations as to physical load are also given on discharge.
- Patients generally return to work in about 1 - 2 months, although timing can vary depending on the severity of the condition.
Emotional RehabilitationDepression occurs in many patients who have ACS or who have had heart attacks. 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, may be very helpful. For some patients, certain types of antidepressant drugs may be appropriate.
The information is provided by the site: www.sibheart.ru