WEDNESDAY, Jan. 16, 2008 (HealthDay News) -- A citywide system in Ottawa, Canada, designed to rush heart attack patients to a specialized center for artery-opening treatment dramatically cut the time it took to perform the potentially lifesaving procedure, cardiologists report.
The procedure is balloon angioplasty, in which a balloon is threaded into a blood vessel and inflated to restore flow in a coronary vessel blocked by a clot. The American Heart Association has set a goal of no more than 90 minutes from diagnosis of a heart attack to angioplasty. And that goal was met for almost 80 percent of the cases handled by specially trained paramedics, according to a report in the Jan. 17 issue of the New England Journal of Medicine.
"We have developed a system in which the paramedics do an ECG [electrocardiogram] in the field," said Dr. Michel R. Le May, professor of medicine at the University of Ottawa Heart Institute, and lead author of the report. "They call through a dedicated cell phone line to the Heart Institute to notify the STEMI team that they are arriving. Then, they go straight to the catheter lab."
STEMI stands for ST-segment elevation myocardial infarction, the deadliest kind of heart attack, and the catheter lab is where angioplasty is done.
The average "door-to-balloon time" for the 135 heart attack patients handled by that specialized system for the year beginning May 1, 2005, was 69 minutes. By contrast, time to treatment for the 209 patients sent from emergency rooms was 123 minutes.
That produced a difference in survival numbers, with six deaths in the following six months for people treated through the paramedic system (4.4 percent), compared to 12 deaths (5.7 percent) for those who went through emergency rooms. The survival figures should be regarded cautiously, Le May said, in part because the numbers were small, and a number of factors affect survival.
A good deal of coordination was needed to set up the system, he said. Ottawa, a city of 800,000, has four major hospitals, and all agreed to have heart attacks handled by the Heart Institute, rather than sending patients to the nearest hospital. Paramedics had to be trained to do electrocardiograms in the field, which was done in collaboration with the four hospitals, and the special telephone lines had to be established, the report said.
The program also includes treatment "in all aspects of cardiology," such as advice on diet and exercise, as well as smoking cessation when necessary, Le May said. Drug therapy for risk factors such as high cholesterol levels and blood pressure is started in the hospital and continued at home.
Careful planning would be needed to start a similar system in a larger city, Le May said.
"In a city with multiple catheter labs, you would have to get cardiologists together to work out a way for patients to be directed to catheter labs," he said. "You would have to sit down and develop specific pathways -- this hospital on this day, that hospital on that day."
And while Ottawa's improvement in survival may not be definitive, "we know from larger studies that there is a good correlation between lower door-to-balloon time and lower mortality," Le May said.
Dr. Alice Jacobs, professor of medicine at Boston University and a spokeswoman for the American Heart Association, said the Ottawa system fits right in with the heart association's program to improve care for STEMI patients.
"The American Heart Association understands that there is not a 'one-size-fits-all' solution," Jacobs said. Local affiliates of the association "are being convened into task forces that are identifying ways to establish national recommendations for STEMI systems on a local level in view of geography, resources and existing legislation and regulation."
It's also "critically important" for people to know what to do when a heart attack occurs in their presence, Jacobs said. She stressed "the importance of avoiding delays at the onset of symptoms and activating the Emergency Medical Service by calling 911, rather than driving themselves, or being driven by family or friends, to the emergency department."
More information
To learn more about the warning signs of a heart attack and what to do, visit the American Heart Association.
