News Release

Early Restoration Of Blood Flow Following A Heart Attack Shown To Improve Long-Term Survival For Patients

Peer-Reviewed Publication

American Heart Association

DALLAS, April 28 -- Getting immediate vessel-opening treatment after a heart attack can help you live longer than previously believed, say researchers in a study published in today's Circulation: Journal of the American Heart Association.

While it's well known that immediately restoring blood flow to the heart following a heart attack provides a short-term benefit, this study is the first to demonstrate that those with early restored blood flow show a significant statistical improvement in survival rates beyond the first 30 days following the heart attack.

The researchers acknowledge previous studies that showed that vessel-opening treatment is better than placebo up to 30 days following the treatment. "But beyond 30 days, the survival curves have been consistently parallel (the same) for the following 1 to 5 years indicating no further treatment advantage," the authors write.

Most people who die of a heart attack do so in the first 24 hours. Immediate restoration of blood flow to the heart after a heart attack -- a process called reperfusion -- is critically important to preserving the main pumping chamber of the heart. The researchers say their study provides evidence strengthening the need for early arrival at a hospital for treatment that can greatly improve chances for a good recovery.

"Successful early reperfusion provides patients with an advantage that continues to increase well beyond the first month after a heart attack," says lead author Allan M. Ross, M.D., director of the Cardiovascular Research Institute at George Washington University in Washington, D.C. "Although cost analysis was not a component of this study, the substantial additional later benefits should be taken into account in consideration of the cost-effectiveness of aggressive treatment strategies."

The researchers found that preserving the function of the left ventricle -- the heart's main pumping chamber -- through early emergency treatment of heart attack saved another 9 lives per 100 in the first month and two more in the first two years following the heart attack when compared to those who did not have preserved function. Of patients with good ventricular function, 3.1 percent died in the first 30 days compared to 12 percent for those with inadequate functioning. The cumulative two-year death rate was 7.2 percent vs. 26.6 percent.

The study performed in the United States, Canada, Australia and Europe among 2,431 patients in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries Trial (GUSTO-I) Angiographic Substudy focused on the outcome of treatment, not the specific reperfusion drug the patients received, says Karin Coyne, R.N., M.P.H., a co-investigator.

People in the study received one of four different commonly used clot-dissolving regimens in the emergency room for treatment of heart attacks. Instead of looking at which treatment provided the best survival rate, researchers examined how well this type of treatment restored the blood flow to the heart and the left ventricle's ability to pump the blood.

The blood flow through the arteries leading to the heart was measured on a scale known as Thrombolysis in Myocardial Infarction (TIMI flow grade). The TIMI grade measures the speed of flow through the coronary arteries on a scale of 0 to 3. TIMI grade 3 is a normal blood flow; TIMI grade 1 is almost no blood getting through.

Quick restoration of blood flow to TIMI 3 saved three lives in a 100 in the first month and another five per 100 in the first two years. These patients had a cumulative death rate of 4.6 percent in the first month, compared to a rate of 8 percent for patients whose reperfusion was not as successful. The two-year death rate comparison was 7.9 percent for early opened arteries against 15.7 percent.

The researchers reported the impact was the same no matter which therapy was used.

The study was coordinated by the George Washington University, Duke University, Durham, N.C., the Cleveland (Ohio) Clinic, Thoraxecentrum in the Netherlands, and University Hospital, Gasthuisberg, Belgium.

Co-authors are Coyne, Eduardo Moreyra, M.D.; Jonathan S. Reiner, M.D.; Samuel W. Greenhouse, Ph.D.; Pamela Walker, R.N.; Maarten L. Simoons, M.D.; Yasmine Draoui, M.S.; Robert M. Califf, M.D.; Eric J. Topol, M.D.; Frans Van de Werf, M.D.; and Conor F. Lundergan, M.D.

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