What is a heart attack?
A heart attack (also known as a myocardial infarction or MI) is the death of heart muscle from the sudden blockage by a blood clot in a coronary artery that supplies blood to the heart. Blockage of a coronary artery deprives the heart muscle of blood and oxygen, causing injury to the heart muscle. Injury to the heart muscle causes chest pain and pressure. If blood flow is not restored within 20 to 40 minutes, irreversible death of the heart muscle will begin to occur. Muscle continues to die for 6 to 8 hours at which time the heart attack usually is "complete." The dead heart muscle is replaced by scar tissue.
Click here to view interactive photos of hearts that have suffered a heart attack.
How is a heart attack treated?
Treatment of heart attacks includes:
- Antiplatelet medications to prevent formation of blood clots in the arteries
- Anticoagulant medications to prevent growth of blood clots in the arteries
- Coronary angiography with either percutaneous transluminal coronary angioplasty (PTCA) with or without stenting to open blocked coronary arteries
- Clot-dissolving medications to open blocked arteries
- Supplemental oxygen to increase the supply of oxygen to the heart’s muscle
- Medications to decrease the need for oxygen by the heart’s muscle
- Medications to prevent abnormal heart rhythms
- Cardiac surgery
The primary goal of treatment is to quickly open the blocked artery and restore blood flow to the heart muscle, a process called reperfusion. Once the artery is open, damage to heart muscle ceases, and pain improves. By minimizing the extent of heart muscle damage, early reperfusion preserves the pumping function of the heart. Optimal benefit is obtained if reperfusion can be established within the first 4 to 6 hours of a heart attack. Delay in establishing reperfusion can result in more widespread damage to heart muscle and a greater reduction in the ability of the heart to pump blood. Patients with hearts that are unable to pump sufficient blood develop heart failure, decreased ability to exercise, and abnormal heart rhythms. Thus, the amount of healthy heart muscle remaining after a heart attack is the most important determinant of the future quality of life and longevity.
Heart Attack Treatment Options
What is the Treatment For Heart Attack?
The 2013 ACCF/AHA guidelines for treatment of a heart attack are summarized as follows:
- Ideally, transport patient to a PCI capable hospital; if not PCI capable, transfer patient as soon as possible and less than 120 min; if anticipated transfer is more than 120 min, give fibrinolytic agent within 30 min of arrival
- Send to cath lab
- Diagnostic angiogram
- PCI (Percutaneous Coronary Intervention) also termed stenting or stent placement
- If reocclusion occurs or perfusion fails in a patient given a fibrinolytic, arrange transfer to a PCI capable facility; for other patients treated with a fibrinolytic, transfer to a PCI facility within about 3-24hrs
- If step 5 occurs, step 3 should follow at a PCI capable facility were either medical therapy, a PCI or a CABG should be done Patients who are not candidates for PCI therapy usually undergo medical or surgical (CABG) therapy. For a more detailed presentation of the medical treatments and CABG, read the heart attack treatment article.
Continue reading more about heart attack »
Antiplatelet agents
Antiplatelet agents are medications that prevent blood clots from forming
by inhibiting the aggregation of platelets. Platelets are fragments of cells
that circulate in the blood. Platelets begin the formation of blood clots by
clumping together (a process called aggregation). Platelet clumps are then
strengthened and expanded by the action of clotting factors (coagulants) that
result in the deposition of protein (fibrin) among the platelets. Aggregation of
platelets occurs at the site of any injury or laceration, but it also occurs at
the site of rupture of cholesterol plaques in the walls of coronary arteries.
Formation of clots at the site of an injury or laceration is desirable because
it prevents excessive loss of blood, but formation of clots inside coronary
arteries blocks the arteries and causes heart attacks.
There are three types of antiplatelet agents — aspirin, thienopyridines, and
the glycoprotein IIb/IIIa inhibitors. These agents differ in their mode of
action, antiplatelet potency, speed of onset of action, and cost. For
more, please read the Aspirin and Antiplatelet
Medications article.
Aspirin
Aspirin inhibits the activity of the enzyme cyclo-oxygenase inside platelets.
Cyclo-oxygenase is an enzyme whose activity is necessary for the formation of a
chemical, thromboxane A2, that causes platelets to aggregate. Aspirin, by
inhibiting the formation of thromboxane A2, prevents platelets from aggregating
and thereby prevents the formation of blood clots.
Aspirin alone has its greatest impact on improving survival among patients
with heart attacks. Numerous studies have shown that aspirin reduces mortality
(by 25%) when given to patients with heart attacks. Aspirin is easy to use, safe
at the low doses used for antiplatelet action, fast acting (with an onset of
action within 30 minutes), and cheap. Aspirin is given at a dose of 160 mg to
325 mg immediately to almost all patients as soon as a heart attack is recognized. It
also is continued on a daily basis indefinitely after the heart attack. The only
reason for not using aspirin is a history of intolerance or allergy to aspirin.
Aspirin is taken daily following a heart attack to reduce the risk of another heart
attack. (Preventing further heart attacks is called secondary prevention, while preventing
the first heart attack is called primary prevention). The ideal daily dose
of aspirin for secondary prevention has not been established. Some doctors recommend
160 mg; others recommend 81 mg. The reason for this difference has to
do with aspirin’s occasional long-term side effect of bleeding (for example from
stomach ulcers). Even though the risk of major bleeding with long-term, moderate
dose aspirin (325 mg/day) is low (less than 1%), this risk can be
lowered slightly by using an even lower dose (160 or 81 mg/day).
Aspirin also benefits patients with forms of coronary heart disease other
than heart attacks. Aspirin has been shown to reduce heart attacks and
improve survival in the following patients:
- Aspirin improves survival among patients with unstable
angina. Patients with unstable angina experience chest pains at rest or with
minimal exertion. These patients have critically narrowed coronary arteries
and are at imminent risk of having a heart attack. - Aspirin improves survival among patients with stable
exertional angina. (These are patients who experience chest pain only with
exertion.) - Aspirin prevents formation of blood clots at the site
of the PTCA (see below). - Aspirin prevents the formation of blood clots that can
occlude surgical bypass grafts. (Occlusion of bypass grafts can lead to heart
attacks.) - Aspirin in low doses (81 mg/day) has been shown to prevent first heart
attacks (primary prevention).
Thienopyridines
Thienopyridines such as ticlopidine (Ticlid), clopidogrel (Plavix), and prasugrel (Effient), inhibit the ADP receptor on the surface of platelets. Inhibiting the ADP receptors on the platelets prevent the platelets from aggregating and causing blood clots to form. The theinopyridines are more potent antiplatelet agents than aspirin. Clopidogrel (Plavix) and prasugrel (Effient) are used far more commonly than ticlopidine (Ticlid) because ticlopidine can, in rare instances, cause low platelet and/or white blood cell counts. These agents play an important role in the treatment of heart attacks and are used in the following situations:
- Clopidogrel or prasugrel is used instead of aspirin in patients who have an allergy to aspirin.
- Clopidogrel or prasugrel are often given together with aspirin in treating heart attacks. Studies have shown that the combination of aspirin and clopidogrel is more effective than aspirin alone in improving survival and limiting damage to heart muscle among patients with heart attacks.
- Clopidogrel or prasugrel is given together with aspirin to patients undergoing PTCA with or without coronary stenting (see later discussion). Studies have shown that the combination of aspirin and clopidogrel is more effective than aspirin alone in preventing formation of blood clots that can re-occlude the coronary artery unblocked by PTCA and in preventing blood clots within recently placed stents.
- After a heart attack or after PTCA, aspirin is given indefinitely. The optimal duration of clopidogrel has not been established, and duration of use by physicians varies from weeks to months.
Patients who receive the combination of clopidogrel and aspirin are more likely than patients who receive aspirin alone to develop complications of major bleeding following coronary artery bypass surgery. Therefore, ideally, clopidogrel should be stopped 3 to 7 days before surgery.
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Glycoprotein IIb/IIIa inhibitors
The glycoprotein IIb/IIIa inhibitors such as abciximab (Reopro) and
eptifibatide (Integrilin) prevent aggregation of platelets by inhibiting the
glycoprotein receptors on the platelets. They are the most potent antiplatelet
agents, approximately 9 times more potent than aspirin, and 3 times more
potent than the thienopyridines. The glycoprotein IIb/IIIa inhibitors are also
the most expensive antiplatelet agents. The currently FDA-approved glycoprotein
IIb/IIIa inhibitors have to be given intravenously. They usually are given along
with aspirin and heparin. They are quick acting; their maximal antiplatelet
effects are achieved within minutes of infusion. These inhibitors have become
important in the treatment of patients with heart attacks, patients with
unstable angina, and patients undergoing PTCA with or without stenting. Numerous
studies have shown that glycoprotein IIb/IIIa inhibitors:
- Decrease the size of the blood clot blocking the
coronary arteries, thus improving blood flow, limiting damage to heart muscle,
and improving survival among patients with heart attacks - Decrease the incidence of heart attacks and improve
survival among patients with unstable angina - Prevent the formation of blood clots inside coronary stents and in
coronary arteries unblocked by PTCA, thus decreasing the incidence of heart
attacks and improving survival, specifically, when given intravenously at the time of PTCA and
stenting and followed by oral aspirin and clopidogrel
The major risk of glycoprotein IIb/IIIa inhibitors is bleeding. Therefore,
patients on heparin, aspirin, and glycoprotein IIb/IIIa inhibitors have to be
monitored closely for bleeding. Recent studies have demonstrated equal efficacy
of abciximab and eptifibatide. Eptifibatide is shorter acting than abciximab. In
the event of major bleeding, the antiplatelet effect of eptifibatide can be
reversed within hours of stopping the intravenous infusion, while the
antiplatelet effect of abciximab will last much longer. Sometimes, transfusions
of platelets are necessary to treat major bleeding due to abciximab.
An uncommon side effect of glycoprotein IIb/IIIa inhibitors is
the development of low platelet counts (thrombocytopenia). Thrombocytopenia
can increase the risk for bleeding and, in rare instances, may actually cause blood to
clot. Thus, patients receiving glycoprotein IIb/IIIa inhibitors should have
their platelet counts monitored closely.
QUESTION
In the U.S., 1 in every 4 deaths is caused by heart disease.
See Answer
Anticoagulants
Coagulants (clotting factors) are proteins produced by the liver. Clotting
factors are responsible for “cementing” clumps of platelets together to form
a stronger and larger clot. Anticoagulants such as intravenous or subcutaneous
heparin, subcutaneous low molecular weight heparin, and oral warfarin
(Coumadin), prevent the formation of blood clots either by inhibiting the
production of clotting factors or by interfering with the action of the clotting
factors.
Heparin prevents
the formation and growth of blood clots by inhibiting the action of clotting factors that
cement the clumps of platelets together. Heparin is given either intravenously
or as a subcutaneous (under the skin) injection.
Heparin commonly is given intravenously, usually with aspirin, antiplatelet
agents, or fibrinolytic (clot-dissolving) medications for treating heart attacks. Intravenous heparin
is given (usually with aspirin or an antiplatelet agent) to patients with heart
attacks who are undergoing PTCA with or without stenting. Heparin also is given
to patients who are at risk of developing blood clots within the chambers (atria
and ventricles) of the heart. (For example, patients with atrial fibrillation
can develop blood clots in the atria. Patients with large heart attacks and major
damage to the heart muscle also can develop blood clots in the ventricles.)
Heparin’s anticoagulant effect is fast acting (beginning shortly after the
start of the infusion) and dose-related (greater with higher doses). The
duration of heparin treatment for heart attacks is approximately 48 hours.
Heparin’s major side effect is bleeding, and the
most serious bleeding complication is intracranial hemorrhage (bleeding into the brain).
The risk of bleeding is higher with higher doses. Thus, patients
receiving heparin will undergo frequent blood testing to measure APPT levels. The APPT
level is a measure of the degree of anticoagulation. The goal is to
keep the patient’s APPT level in a safe range and to avoid abnormally high
APPT levels that signify excessive anticoagulation and a greater risk of
bleeding. If there is bleeding, heparin has the advantage of having a short duration
of action and its anticoagulant effects disappear rapidly
after stopping the intravenous infusion.
Low molecular weight heparins such as
enoxaparin (Lovenox) and dalteparin (Fragmin),
are sub-fractions of heparin with longer-lasting effects than heparin. They can be given every
12 to 24 hours as subcutaneous injections (like insulin). Studies have shown
enoxaparin and dalteparin to be equivalent to intravenous heparin in patients with
many conditions such as heart attacks, unstable angina, and blood clots in the
veins or arteries of the lungs. The effects of low molecular weight heparins
generally wear off after 6 to 12 hours. They are not used in place of intravenous heparin in
patients undergoing PTCA or stenting.
Warfarin (Coumadin)
prevents the formation of blood clots by inhibiting the production of clotting factors by the
liver. Warfarin must be taken orally and is slow acting; it can
take days to achieve an adequate anticoagulant effect. Warfarin’s anticoagulant effect is dose-related, that
is, its effect is greater with larger doses.
Because of its
slow onset of action, Coumadin is not commonly used immediately for the treatment
of heart attacks. Instead, it is used orally on a long-term basis in selected
patients after heart attacks to prevent blood clots. For example, patients with
atrial fibrillation or patients with major damage to ventricular muscle will
take warfarin daily on a long-term basis to prevent blood clots in
the atria and ventricles, respectively. Warfarin also is commonly used to prevent blood
clots in veins of the legs in patients who are likely to develop them.
The risk with warfarin is abnormal bleeding, and the risk of bleeding is higher with higher doses.
Thus, patients on warfarin should have their blood tested frequently (often
weekly) to measure their prothrombin time and INR. Like APPT, the prothrombin
time and INR measure the degree of anticoagulation. The goal of treatment
is to keep the prothrombin time and INR in a safe range, avoiding excessively
high prothrombin time and INR levels that indicate too much anticoagulation and
a greater risk of bleeding. The effects of warfarin may be increased or
decreased greatly by many other medications or foods, and it is crucial to review
these medications and foods with the doctor.
Warfarin has a long duration of action, and its anticoagulation effect can last several days after it is
stopped. Therefore, transfusions of clotting factors and/or vitamin K (to stimulate the
liver to produce the clotting factors depleted by treatment with warfarin) must be
given to reverse the anticoagulation in the event of serious bleeding.
Direct thrombin inhibitors are newer oral anticoagulants that have recently been introduced, such as rivaroxaban (Xarelto) and dabigatran (Pradaxa), which don’t require the monitoring and dietary restrictions of warfarin, and their role is under investigation.
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Clot-dissolving drugs
While antiplatelet agents and anticoagulants prevent the formation of blood
clots, they cannot dissolve existing blood clots and hence cannot be relied upon
to open blocked arteries rapidly. Clot-dissolving drugs (also called
fibrinolytic or thrombolytic medications) actually dissolve blood clots and can
rapidly open blocked arteries. Intravenous administration of clot-dissolving
drugs such as tissue plasminogen activator (TPA) or TNK can open up to 80% of
acutely blocked coronary arteries. The earlier these drugs are administered, the
greater the success at opening the artery and the more effective the
preservation of heart muscle. If clot-dissolving drugs are given too late (more
than 6 hours after the onset of the heart attack), most of the muscle damage
already may have occurred.
If a hospital does not have a catheterization laboratory with the ability to
perform PTCA, or if there are logistic reasons why PTCA will be delayed,
clot-dissolving drugs can be promptly administered to achieve reperfusion. PTCA
then may be performed in patients who fail to respond to the clot-dissolving
drugs. (If prompt PTCA and stenting are available, it has been demonstrated that
they are preferable to clot-dissolving drugs to open arteries.)
Clot-dissolving drugs increase the risk of bleeding enough so that some patients cannot be
treated with them, for example, patients with recent surgery or major trauma,
recent stroke, bleeding ulcer, or other conditions that increases the risk of
bleeding.
Coronary angiography and percutaneous transluminal coronary angioplasty (PTCA)
Coronary angiography and percutaneous transluminal coronary angioplasty (PTCA) is the most direct method of opening a blocked coronary artery. The procedures are performed in the catheterization laboratory in a hospital. Under X-ray guidance, a tiny plastic catheter with a balloon on its end is advanced over a guide wire from a vein in the groin or the arm and into the blocked coronary artery. Once the balloon reaches the blockage, it is inflated, pushing the clot and plaque out of the way to open the artery. PTCA can be effective in opening up to 95% of arteries. In addition, the angiogram (X-ray pictures taken of the coronary arteries) allows evaluation of the status of the other coronary arteries so that long-term treatment plans may be formulated.
For optimal benefits, coronary angiography and PTCA should be performed as soon as possible. Most cardiologists recommend that the time interval between the patient's arrival at the hospital and the deployment of the angioplasty balloon to open the artery should be less than 60 to 90 minutes.
For best results, the coronary angiogram and PTCA should be performed by an experienced cardiologist in a well-equipped cardiac catheterization laboratory. The cardiologist is considered experienced if he or she performs more than 75 such procedures a year. The catheterization laboratory personnel are considered experienced if the facility performs more than 200 such procedures a year.
It also is important that there be a surgical team to perform immediate open-heart surgery (coronary artery bypass grafting) in the event that PTCA is unsuccessful in opening the blocked artery or if there is a serious complication of PTCA. For example, in a small number of patients, PTCA cannot be performed because of technical difficulties in passing the guide wire or the balloon across the narrowed arterial segment. Open-heart surgery also will be necessary if there is a serious complication such as coronary artery injury during PTCA or an abrupt closure of the coronary artery shortly after PTCA. These complications may occur in a small percentage of patients.
The most serious complication of PTCA is an abrupt closure of the coronary artery within the first few hours after PTCA. Abrupt coronary artery closure (that can lead to further heart damage) occurs in some patients after simple balloon angioplasty (without stenting). Abrupt closure is due to a combination of tearing (dissection) of the inner lining of the artery, blood clotting at the site of the balloon, and constriction (spasm) or elastic recoil of the artery at the site where the balloon is inflated. Individuals at an increased risk for abrupt closure include women, patients with unstable angina, and patients having heart attacks.
The risk of abrupt closure of the coronary arteries can be reduced if:
- Aspirin is given during or after PTCA to prevent blood clotting. In fact, virtually all patients are maintained on aspirin indefinitely after PTCA to prevent arterial clots.
- Anticoagulants such as intravenous heparin or bivalirudin are given during PTCA to further prevent blood clotting.
- Combinations of nitrates and calcium channel blockers are used to minimize coronary artery spasm (see discussion that follows).
- Coronary artery stents are deployed to minimize coronary artery closure.
- The glycoprotein IIb/IIIa inhibitors are given.
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Coronary artery stents
Coronary artery stents are small hollow cylinders that can be deployed over the angioplasty balloons and left within the coronary arteries to keep the arteries open. Stents help prevent abrupt closure of arteries shortly after PTCA. They also prevent restenosis (recurrent narrowing of the arteries) several months after PTCA.
Coronary stents decrease the risks of arterial dissections, elastic recoil, and artery spasm that can occur after PTCA and cause re-occlusion of the artery. Studies have shown that the incidence of abrupt coronary artery closure after PTCA has declined dramatically with the introduction of coronary stents.
Coronary stents also help to keep the coronary arteries open in the longer-term. After a successful PTCA, a significant percentage of patients will develop recurrent narrowing (restenosis) at the site of inflation of the balloon, usually within 6 months following PTCA. Restenosis may or may not be accompanied by symptoms such as angina. Thus, restenosis often is detected by exercise stress tests performed 4 to 6 months after PTCA. The widespread use of coronary stents has reduced this incidence of restenosis. The introduction of coated stents (stents that are coated with chemicals to further reduce restenosis) has reduced the incidence of restenosis to well under 10% and has been a major improvement in treatment.
Patients with coronary artery stents usually are maintained on full doses of daily aspirin. For the first 4 to 12 weeks after the placement of stents, patients are given an additional antiplatelet drug such as clopidogrel or prasugrel because the metal surface of the stents may promote the formation of blood clots in the first several weeks after the stent is inserted. With medicated stents, aspirin and clopidogrel or prasugrel are continued for a year or longer.
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Heart Attack Treatment
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Nitrates
Nitroglycerin is the most common nitrate used in the treatment of heart attacks. It
can be given sublingually (under the tongue), as a spray, as a paste applied
over skin, and intravenously. Intravenous nitroglycerine has a rapid onset
of action and is commonly used in the initial (first 48 hours) treatment of
heart attacks. Nitroglycerine is a vasodilator (blood vessel expander), that opens
arteries by relaxing the muscular wall of the artery. Nitroglycerine dilates
coronary arteries as well as other blood vessels throughout the body. By dilating
blood vessels, nitroglycerine lowers blood pressure, decreases the work
that the heart must do to pump blood, lowers the demand by the heart for oxygen, prevents
coronary artery spasm, improves blood flow to the heart muscle, and potentially
minimizes the size of the heart attack. Nitroglycerine is especially helpful in
patients with heart attacks who also have heart failure or high blood pressure.
The common side effects of nitrates are headaches and low blood pressure. Low
blood pressure can cause weakness, dizziness, and, sometimes, even fainting.
Nitrates should not be given in patients who have taken medicines for erectile
dysfunction such as sildenafil (Viagra) and vardenafil
(Levitra) in the
preceding 24 hours, since severe low blood pressure may result. Nitrates should
not be given in patients who have taken tadalafil (Cialis) in
the preceding 36 to 48 hours
because the effects of Cialis last longer than either sildenafil or
vardenafil.
Angiotensin converting enzyme (ACE) inhibitors
Angiotensin
converting enzyme (ACE) inhibitors, another class of blood vessel dilators,
often are given orally after a large heart attack to improve the healing of
heart muscle. Examples of ACE inhibitors include captopril (Capoten), enalapril
(Vasotec), lisinopril (Zestril and Prinivil), and ramipril (Altace). These
medications lower the blood pressure and reduce the workload of the heart,
thereby helping the damaged heart muscle to recover. They are especially helpful
in patients who have recovered from heart attacks but have high blood pressure,
heart failure, major damage to the left ventricle, and diabetes mellitus.
For additional information, please see the ACE
Inhibitors article.
Beta blockers
Beta blockers such as propranolol (Inderal), metoprolol (Lopressor, Toprol
XL), and atenolol (Tenormin)
usually are given early during a heart attack and are continued
long-term. Beta blockers antagonize the action of adrenaline and relieve stress
on the muscles of the heart. Beta blockers decrease the workload of
the heart by slowing the heart rate and decreasing the force of contraction of
heart muscle. Decreasing the workload decreases the demand for oxygen by
the heart and limits the amount of damage to the heart muscle. Long-term administration of
beta blockers following a heart attack has been shown to improve
survival and reduce the risk of future heart attacks. Beta blockers also improve survival
among patients with heart attacks by decreasing the incidence of
life-threatening abnormal heart rhythms, for example, ventricular fibrillation.
Beta blockers can be given intravenously in the hospital and then can be taken
orally for long-term treatment.
The side effects of beta blockers are wheezing
(worsening of breathing in patients with
asthma), abnormally slow heart rate,
and exacerbation of heart failure (especially in patients with significant
damage to their heart muscle); however, in patients with chronic heart failure,
beta blockers have recently been demonstrated to be helpful in decreasing
symptoms and prolonging life. For more, please read the
Beta Blockers article.
Oxygen
Oxygen also is commonly administered during the acute phase of a heart
attack as are narcotics such as morphine; these agents aid in the reduction of
discomfort and actually help minimize the amount of heart damage.
Coronary artery bypass
In some patients, PTCA can be technically difficult or dangerous to perform.
In others, PTCA and clot-dissolving medications may fail to achieve reperfusion
or maintain open arteries. These patients may be considered for coronary artery
bypass grafting surgery. For more information, please see the Coronary Artery
Bypass Graft article.
What can a patient expect during recovery from a heart attack?
Heart attack patients are monitored in the hospital for 3 or more days
prior to discharge home. Rhythm disturbances, shortness of breath due to heart
failure, or recurrent chest pain are reasons for further therapy such as balloon
angioplasty or coronary stenting, additional medications, or bypass surgery.
Patients gradually increase their activity under observation. Before
discharge, a low-level exercise stress test may be performed to detect important
residual narrowing in the coronary arteries, exercise-induced cardiac rhythm
abnormalities, and heart muscle failure, and to help guide the doctor in
prescribing an activity regimen after hospitalization. An abnormal stress test
prior to hospital discharge following a heart attack predicts a high risk for
subsequent cardiac events; if the patient has not yet had a coronary angiogram,
an abnormal pre-discharge stress test is a strong reason for doing angiography.
Since most patients usually receive angiography early, the use of pre-discharge
stress testing has declined.
Before resuming full activity or work, several weeks may
be needed for the heart muscle to heal. After a small heart
attack (little damage to heart muscle), patients usually can resume
normal activities after 2 weeks. These activities include returning to work as
well as normal sexual activity. A moderate heart attack
(moderate damage to heart muscle) requires limited, gradually increasing
activity for up to 4 weeks, while a large heart attack (much damage to heart muscle) may result in a recovery period of
6 weeks or
longer. These time frames are necessary in order for the dead heart muscle to
substantially complete the scarring process. During this healing period,
patients should avoid vigorous exertion and heavy lifting (over 20 pounds) or
any strenuous activity that causes shortness of breath or undue fatigue.
Cardiac rehabilitation typically begins during hospitalization and continues
during the months following a heart attack. Cardiac rehabilitation programs
provide a helpful transition to a safe and full return to a normal lifestyle. In
addition, cardiac rehabilitation allows the prescription of a long-term exercise
program tailored to each patient and helps patients and their families adjust to
lifestyle changes and the difficult and conflicting emotions that often follow a
heart attack.
How can a second heart attack be prevented?
- Take aspirin and beta blockers (propranolol, metoprolol, atenolol) that have been shown to reduce the chances of a second heart attack and improve survival.
- Stop smoking cigarettes.
- Reduce excess weight and exercise regularly.
- Control blood pressure and diabetes.
- Follow a diet that is low in cholesterol (less than 200 mg daily) and saturated fat (less than 7% of total calories). For more, please see the Therapeutic Lifestyle Changes (TLC) Daily Food Guide, Eating Heart Healthy.
- Reduce LDL (bad) cholesterol and increase HDL (good) cholesterol. Reduction of LDL cholesterol to a value below 80 mg/dl, particularly with the statin group of medications, has been demonstrated to prevent further heart attacks. Patients with low HDL (less than 35 mg/dl) are encouraged to exercise regularly and to take medications to increase HDL. For more in-depth information about cholesterol, LDL, and HDL, please see the Cholesterol article.
- Take ACE inhibitors that aid the healing process and improve long-term survival in selected patients, particularly those with major damage to heart muscle.
- Eat a diet rich in omega-3-fatty acids by eating more fish or take fish oil supplements. (See the fish oil article). High intake of omega-3-fatty acids decreases the risk of sudden death from heart attacks.
- Undergo further testing. In the months following a heart attack, further cardiac stress testing, with or without nuclear or echocardiographic imaging, may be prescribed to determine if additional therapy will be necessary to prevent future heart attacks. In addition, special testing may be required to evaluate the risk of developing cardiac arrhythmias. All such testing should be discussed with the doctor.