Heart 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, 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 will occur, patients can avoid having another heart attack by 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.
Heart attack also increases the risk for other heart problems, including heart failure, 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 heart disease
- 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 is highest in younger women.
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:
- 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 cellular abnormalities. Shock occurs in about 7% of heart attacks.
- Heart block, also called atrioventricular (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.