Heart attack survivor Robert Steele sits in the back of an ambulance yesterday with paramedic Stacey Allen his wife Carmen Steele, paramedic Michel Houle and Dr. Paul Armstrong. A clot-busting drug, administered by paramedics under a program developed in Edmonton, saved his life.
Credits: DAVID BLOOM/QMI AGENCY
An international study led by U of A professor and senior cardiologist Dr. Paul Armstrong has found patients who receive "clot-busting" drugs within three hours of a heart attack, followed by an angioplasty, do as well as patients who only receive the angioplasty within three hours.
The Strategic Reperfusion Early After Myocardial Infarction (STREAM) study was published in the New England Journal of Medicine on Sunday while the study's co-lead, Belgian researcher Frans Van de Werf, presented the findings at American College of Cardiology conference in San Francisco.
"We think they're very significant," Armstrong said. "We have been looking at it for almost five years."
The topic of which of the two methods are superior for treating heart attacks has been highly contested in the cardiovascular medical field, Armstrong said.
While many have believed the angioplasty-only approach is superior, it is also less accessible because it needs to be administered as soon as possible by specialists in a tertiary care hospital, of which only three exist in Alberta.
In many parts of the world, access to specialized catheter angioplasty facilities is very limited. Armstrong said delays while waiting for angioplasty without drugs can lead to a loss of heart muscle and ultimately higher rates of death.
Angioplasty uses a catheter to open a blocked coronary artery, while the clot-busting drugs can be administered in the ambulance by a paramedic.
"We need to move the goal posts out into the community faster to the patients. Because of course we have been spectacularly unsuccessful in modifying human behaviour and getting them to come to the hospital more quickly," he said.
"The fact that we shaved nearly an hour off the conventional time to treatment, getting them treated very early, in either case we think was rewarded with a fairly low mortality rate."
Armstrong's study used 1,900 patients from 15 countries, including 65 patients from Edmonton, and followed them for 30 days after their treatments. Half were treated with the clot-busting drugs, followed by an angioplasty, and the other half just had angioplasties within three hours. Researchers measured the patients' likelihood of shock, recurrent heart attacks, and heart failure.
Armstrong expects the findings to be put to use immediately in the medical field. His team will continue to work with the patients and publish updated findings next year.