More Canadians die after heart attack: Study
FROM CANADIAN PRESS

Canadians have a greater risk of dying within five years after a
common type of heart attack than their American cousins, a study
comparing treatments in the two countries suggests.
The research, to be published in an upcoming issue of Circulation:
Journal of the American Heart Association, suggests that more
conservative treatments in Canada may be behind the difference in
survival rates, said Padma Kaul, an epidemiologist at the University
of Alberta and lead investigator of the study.
Kaul found that within five years of initial treatment for a heart
attack caused by a completely blocked coronary artery (about one-
third of heart attacks are this type), the U.S. patients had a death
rate of 19.6 per cent versus 21.4 per cent for the Canadians.
That roughly two per cent difference may seem small, but on a
population basis, it could represent thousands of lost lives.
"One possible explanation is the difference in the revascularization
rates between the two countries, and those were significantly
different," said Kaul, explaining that U.S. doctors perform about
three times the number of angioplasties and coronary bypass surgeries
done by Canadian physicians.
With angioplasty, a tiny balloon is threaded into a plaque-narrowed
artery, then inflated to compress the obstruction and open up blood
flow. Bypass surgery reroutes the blood through a blood vessel —
often a vein taken from the leg — that's grafted to the coronary
artery feeding the heart. Both procedures are known as
revascularization.
Almost one-third of the U.S. patients had angioplasty after a heart
attack, compared to 11.4 per cent in Canada. More than 13 per cent of
those in the U.S. group had bypass, while just four per cent of
Canadian patients were referred for the open-heart surgery.
"Traditionally, I think, the U.S. practises way more aggressively
than Canadian practice in terms of using revasc procedures, and
that's been shown repeatedly," Kaul said from Edmonton, noting that
Canadian physicians are more apt to treat heart attack patients with
only clot-busting drugs like TPA and streptokinase.
Her study was an expansion on earlier research from 1990-1993 that
examined heart function, quality of life and survival for Canadian
and American patients after treatment for a heart attack. That study
compared health outcomes after using different clot-busting drugs
either alone or in combination. Doctors also ordered angioplasty or
bypass at their discretion, she said.
After one year, the earlier study found that U.S. patients had better
outcomes for heart function and quality of life, said Kaul. However,
the difference in survival at one year was less than half of one per
cent — not enough to suggest changes in practice, she said.
But in 2002, Kaul analysed records from 23,000 Americans and almost
2,900 Canadians in the original study to determine how many were
still alive within five years of initial treatment.
Even though the Canadian patients had better health profiles overall —
fewer had diabetes or high blood pressure, for instance — survival
rates were higher for the U.S. patients.
"While the United States and Canada share a common border, these two
countries differ substantially in how they organize, deliver and pay
for health care," Kaul said.
"The Canadian system is very centralized and we have fewer centres
that provide revascularization services . . . We have a hub-and-spoke
kind of design where we bring all the patients to central centres
where the procedures are done, whereas the U.S. has much more
dispersed facilities across the country."
As well, the study showed Canadian physicians were more likely to
send heart attack patients home with a prescription for beta blockers
to regulate their heart rate (62 per cent), compared with U.S.
patients (53 per cent).
Toronto cardiologist Dr. Beth Abramson, a spokeswoman for the Heart
and Stroke Foundation of Canada, said the two per cent differential
in death rates "suggests that the traditionally conservative Canadian
approach may not be the best to care for our cardiac patients."
"It's a small percentage, but very important when we look at the
cause of death amongst Canadians," Abramson said Monday. "This can
translate into thousands of lives."
While Canadian physicians are performing more angiograms (a
diagnostic procedure to detect artery blockage), angioplasties and
bypass operations than they were 10 years ago, access to operating
rooms and labs to perform angiograms and angioplasties still lags
behind demand — and falls far short of what's available in the United
States, experts say.
"I would strongly suspect that the difference in practices seen
between Canada and the U.S. in this paper are a reflection of a
different health-care system and the funding for infrastructure and
various procedures in the system," Abramson said.
Kaul said large population-based studies are needed to confirm the
results of her study.
"The good news is that we are doing more (revascularizations), so
clinical practice has changed since the early '90s," she said.
``Whether we've addressed this gap is something that we are still
going to keep working at."