If you are having a heart attack, the goal of your health care team will be to prevent permanent heart muscle damage by restoring blood flow to your heart as quickly as possible. If you are transported to the hospital in an ambulance, you will be given oxygen therapy and probably nitroglycerin or a pain reliever, such as morphine.

Additionally, aspirin (which is usually chewed on the way to the hospital or in the emergency room), heparin, and other antiplatelet drugs are given to prevent clots from growing. Other medicines will be given initially to decrease your heart’s workload, improve its pumping function, and treat life-threatening abnormal heartbeats if they occur.

The time it takes to get to a hospital is critical because angioplasty and/or stenting to open blocked arteries or “clot-busting” thrombolytic medicines to dissolve clots are most effective if used within the first several hours after symptoms start. Thrombolytics are given through an intravenous line and travel to the coronary arteries where they break up clots.

Numerous studies have shown that percutaneous coronary intervention saves lives—20 lives for every 1,000 people treated—when compared with treatment with thrombolytics. But experts do not know yet how safe the drug-eluting stents are over the long term or how well they work over the long term.

Although angioplasty with or without stenting is usually the preferred treatment, it is not available at all hospitals and needs to be done within 12 hours after onset of symptoms. As a result, some communities are training paramedics to identify people who have signs of heart attack so that they can be transported directly to a heart center, even if it means bypassing a closer hospital.

If angioplasty with or without stenting is not possible, either because of the location of the blockage or because of numerous blockages, emergency coronary artery bypass surgery may be done.