Ask Dr. K: Time is of the essence in treating heart attack

A heart attack occurs when one of the coronary arteries, blood vessels that supply the heart, becomes fully or partially blocked. The blood carries nutrition — oxygen, sugar and other molecules — that every tissue needs to survive. It also carries away the waste material made by the cells. Any tissue that is completely deprived of a blood supply dies. That includes the heart muscle. (I’ve put an illustration of this process on my website, AskDoctorK.com.)

If you think you may be having a heart attack, call 911. Don’t ask a friend or relative to drive you to the hospital. An ambulance will take you to the emergency department (ED).

When you arrive at the ED, the staff have three immediate challenges:

— They need to assess how sick you are.

— They need to collect information to make the diagnosis: Are your symptoms caused by a heart attack or by another condition?

— They need to give you treatments to relieve your suffering and to minimize the heart damage, if you are indeed having a heart attack.

The ED staff will immediately check your pulse and blood pressure and will take your electrocardiogram (ECG), if you haven’t already had one in the ambulance. They also will take a blood sample for various diagnostic tests.

Physicians will use the ECG, along with blood tests and your symptoms, to confirm that you are having a heart attack or to diagnose another condition that is the cause of your symptoms.

If you are having a heart attack, the doctors will start an intravenous line so that they can rapidly give you medicines. They will hook you up to a heart monitor to identify the development of dangerous heart rhythms. Finally, they usually will give you oxygen, aspirin and possibly other medicines to minimize heart damage.

When I was a medical student, there was not much more that could be done. Specifically, there was no way to open up the blockage in the coronary arteries that was causing the heart attack. Today, there are powerful new treatments for restoring blood flow to the heart and preventing further blockages.

One way to restore blood flow is to perform a procedure called angioplasty. Another way is to administer intravenous clot-busting drugs. Time is of the essence: The faster blood flow is restored to the heart, the greater your chances of surviving and recovering.

As soon as you are stable, you’ll be encouraged to sit up and then stroll the halls. This helps keep blood clots from forming and begins to strengthen your heart.

It sounds frightening. But if you have a heart attack and reach the hospital in time, chances are very good that you will survive — and walk out of the hospital within a week.

(Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.)