Treating A Heart Attack - Dealing With A Heart Attack: Heart Disease

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Treating a heart attack

If you have a heart attack and reach the hospital in time, chances are very good that you will walk out of the hospital within a week or even sooner.

First, you'll probably go to an intensive-care unit (or coronary-care unit), where there are nurses and doctors with specialized training, and equipment to monitor your condition and to treat emergencies. For the first few days after a heart attack, you'll probably need to rest in bed and have your heartbeat continuously monitored to make sure that no dangerous rhythms develop. You may need supplementary oxygen to fuel your heart muscle and an intravenous (IV) line in your hand or arm so you can receive medications.

Treatment of a heart attack involves several strategies conducted almost simultaneously:

• reopening the blocked artery (reperfusion)

• preventing further blood clots from developing

• reducing the oxygen needs of the heart muscle

• monitoring for and controlling complications

• treating any complications that develop

• assessing risk.

Reopening the blocked artery

During the early, acute stages of a heart attack, heart cells are dying rapidly from a lack of oxygen. Therefore, the immediate goal of treatment is to restore blood flow to the heart, by reopening the blocked artery and preventing further blood clots from developing. Such reperfusion therapy can restore the flow of oxygen-rich blood to the heart muscle, sometimes before any serious damage occurs.

There are two ways to restore blood flow: with clot-busting medications and with angioplasty plus stenting. In general, the treatment of choice is now angioplasty with stent insertion (see "Angioplasty"), simply because it saves more lives than clot-busting drugs. Studies report that angioplasty reduces risk for death following a heart attack by about 35%–55% when compared with clot-busting medications. Angioplasty is also better at preventing repeat heart attacks and doesn't cause bleeding in the brain, a possible side effect of drug therapy. But if a cardiac team is not available or the hospital is not equipped to do angioplasty, clot-busting drugs provide another life-saving option (see "Medications for heart disease").

In general, the treatment of choice is now angioplasty with stent insertion.

Time is of the essence in all cases, however: The faster blood flow is restored to the heart, the greater your chances of surviving and recovering. The experts recommend that people diagnosed with ST-elevation myocardial infarction receive clot-busting drugs within 30 minutes of arrival at the hospital, or, even better, that they undergo angioplasty with stent insertion within 90 minutes. In people diagnosed with non-ST-elevation myocardial infarction, or with unstable angina, the situation is not quite so dire and you may be monitored for a longer period before your doctors recommend a particular treatment.

Medications given to open blocked arteries — which also prevent additional blood clots from forming — include aspirin (which helps prevent new blood clots), thrombolytic agents (also called "clot busters" because they help break down clots in blood vessels), and heparin (a stronger clot-preventing agent). On the other hand, these drugs can cause bleeding complications in people over age 70 and in younger people with a history of strokes or certain other conditions (see "Medications for heart disease").

Minimizing the heart's oxygen needs

At the same time that blood flow is being restored, doctors take steps to minimize the heart's oxygen needs. During the first few hours after a heart attack, bed rest helps reduce the heart's oxygen requirements. In addition, medications are given to reduce the heart's workload in several ways. These medications include beta blockers, nitrates, analgesics and sedatives, angiotensin-converting–enzyme (ACE) inhibitors, and angiotensin-receptor blockers (ARBs). See "Medications for heart disease" for a discussion of these drugs.

Monitoring and follow-up

After the immediate treatment for heart attack, doctors monitor your heart for rhythm abnormalities and other heart problems. In the coronary-care unit, nurses are highly trained to recognize electrical disorders and to administer heart drugs. An array of devices and machines — defibrillators, ventilators, pacemaker equipment, and other tools for monitoring and maintaining heart function — stand at the ready.

Most people don't have major problems after a heart attack and can leave the coronary-care unit for a step-down unit, or intermediate-care unit, within a day or two. Intermediate-care units have much of the same monitoring equipment as the coronary-care units; the difference is in the ratio of nurses to patients. In the intermediate-care unit, each nurse cares for three to five patients, compared with only two in the coronary-care unit.

The last step in the hospital phase of treatment is evaluating your risk of having another heart attack — and teaching you how to minimize that risk. This risk assessment involves several types of tests.

Because inflammation is now understood to be central to heart disease, your doctor is likely to order a blood test for C-reactive protein (see "C-reactive protein") to use along with other blood test results (such as for troponin) to better assess your risk of having another heart attack. Studies indicate that people who have just had a heart attack and have a CRP level of 10 mg/dL or greater when they are admitted to the hospital — or who have a CRP level of 3 mg/dL or more after they are stabilized — are at high risk of having another heart attack or dying from heart disease, and presumably would benefit from more aggressive therapy.

After four or five days in the hospital, people whose initial recovery period has been uncomplicated will undergo a low-level exercise tolerance test. The low-level test differs from the conventional exercise tolerance test (see "Exercise tolerance test") in that you will stop exercising after a predetermined number of minutes of low-level exercise on a treadmill, even if you show no problems or symptoms.

The goal of this limited exercise test is to determine whether you are sufficiently stable to resume a reduced level of physical activity at home. If the test is negative — that is, it reveals no problems — you'll be able to go home. The exercise test can also help you learn how much exertion is safe and appropriate during the next phase of the healing period. Most people are reassured to learn that the period of imminent danger has passed and that they can resume a fairly normal life over a period of several weeks.

A low-level exercise test that reveals abnormalities — such as chest pain, fluctuations in heart rhythms, or changes in blood pressure — generally indicates that parts of the heart remain at risk for further damage. In such cases, cardiologists may suggest cardiac catheterization, which can reveal whether angioplasty (see "Angioplasty") or bypass surgery (see "Coronary artery bypass surgery") might improve blood flow to the heart and reduce the chances of another heart attack.

Last updated:	May 03, 2007