March 19, 2010
Questions and answers: After a Heart Attack
Editor’s note: The following article was prepared by Trista Neisen, associated with St. Mary’s Medical Center in Evansville, for publication in the Message. The source of the information below is the American Heart Association. (Related story: St. Mary’s honored for care of heart attack patients)
If you are one of the tens of thousands of Americans that survived a heart attack, you’re probably wondering what happens next. The following questions and answers will help you better understand what happened and what recovery will entail.
Why did I have a heart attack?
A heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or cut off completely. This happens because coronary arteries that supply the heart with blood can slowly become thicker and harder from a buildup of fat, cholesterol and other substances that together are called plaque. This slow process is known as atherosclerosis.
When a plaque in a heart artery breaks, a blood clot forms around the plaque. This blood clot can block the artery and shut off blood flow to the heart muscle. When the heart muscle is starved for oxygen and nutrients, it is called ischemia. When damage or death of part of the heart muscle occurs as a result of ischemia, it is called a heart attack or myocardial infarction (MI).
Why didn’t I have any warning?
Atherosclerosis has no symptoms. One reason there may be no warning signs is that sometimes when a coronary artery becomes narrowed, other nearby vessels that also bring blood to the heart sometimes expand to help compensate. The network of expanded vessels is called collateral circulation and helps protect some people from heart attacks by getting needed blood to the heart. Collateral circulation can also develop after a heart attack to help the heart muscle recover.
Is my heart permanently damaged?
When a heart attack occurs, the heart muscle that has lost blood supply begins to die. The amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery and the time between injury and treatment. Damage to the heart muscle from a heart attack heals by forming scar tissue. It usually takes a month to several weeks for your heart muscle to heal. The length of time depends on the extent of your injury and your own rate of healing.
The heart is a very tough organ. Even though a part of it may have died, the rest keeps working. But because your heart has been damaged, it is weaker and can’t pump as much blood as usual. However, with proper treatment and lifestyle changes, further damage can be limited or prevented.
Will I recover from my heart attack?
The answer is most likely yes. The heart muscle begins to heal soon after a heart attack and usually takes about eight weeks. Scar tissue will form in the damaged area, and that scar tissue does not contract or pump as well as healthy muscle tissue. That means the heart can’t pump as well as before.
The degree of loss of function depends on the size and location of the scar tissue. Most heart attack survivors have some degree of coronary artery disease (CAD) and will have to make important lifestyle changes and possibly take medication to prevent a future heart attack and lead a full, productive life.
Is all chest pain a heart attack?
No. One very common type of chest pain is called angina, or angina pectoris. It’s a recurring discomfort that usually lasts only a few minutes. Angina occurs when your heart muscle doesn’t get the blood supply and oxygen that it needs. The difference between angina and a heart attack is that angina attacks don’t permanently damage the heart muscle. However, angina left untreated can lead to a heart attack.
Often angina occurs during exercise or emotional stress when your heart rate and blood pressure increase and your heart muscle needs more oxygen. Angina becomes more worrisome if it occurs at rest.
Are there other causes of heart attack besides blockage?
Sometimes a coronary artery temporarily contracts or goes into spasm. When this happens the artery narrows and blood flow to part of the heart muscle decreases or stops. A spasm can occur in normal-appearing blood vessels as well as in vessels partly blocked by atherosclerosis. A severe spasm can cause a heart attack.
Is a heart attack the same as cardiac arrest?
No. Heart attacks are caused by a blockage that stops blood flow to the heart, but a heart attack can lead to a cardiac arrest. Cardiac arrest can also be the result of the heart’s electrical system malfunctioning. In cardiac arrest, death results when the heart suddenly stops working properly. This is caused by abnormal, or irregular, heart rhythms called arrhythmias.
The most common arrhythmia in cardiac arrest is ventricular fibrillation. This is when the heart’s lower chambers suddenly start beating chaotically and don’t pump blood. Death occurs within minutes after the heart stops. This may be reversed if CPR is performed and a defibrillator is used to shock the heart and restore a normal heart rhythm within a few minutes.