The Case For Clearing More Arteries During Heart Attacks
An aggressive approach to preventing heart attacks could be the next big thing in the long battle against this leading cause of death.
A British study presented Sunday in Amsterdam finds that doctors can reduce future heart attacks and cardiac deaths by opening up multiple clogged coronary arteries while they're fixing the artery that's causing a heart attack in progress.
The stakes are big. Every year, at least a quarter-million Americans have a deadly kind of heart attack, called STEMI, that is the focus of the new study.
The details, which were published online by the New England Journal of Medicine, show that preventive treatment of partially blocked arteries in these patients avoids 65 percent of future heart attacks, cardiac deaths and cases of recurrent chest pain that warns of imminent attacks.
Under the current standard of care, doctors use a tiny balloon to open up the so-called culprit artery at the earliest possible moment in patients having STEMI heart attacks. That halts the attacks, protects heart muscle from damage, and often saves a lives.
Until now, doctors have believed that it doesn't help to open up other partially blocked coronaries at the same time, says Dr. Laura Mauri of Brigham and Women's Hospital in Boston, even though they can see other arteries are dangerously narrowed.
"Cardiologists have refrained from treating anything" but the total blockage causing the immediate heart attack, Mauri writes in a New England Journal of Medicine editorial that accompanies the British study. "They usually withhold further treatment unless a patient is symptomatic."
The new study, which involved 465 patients with STEMI heart attacks in five U.K. hospitals, could very well change that. Its results were so strong that ethics monitors called an early halt to the trial in January.
The study authors say the results make clear that preventive unblocking of arteries narrowed by more than 50 percent "is a better strategy than restricting further intervention" to those suffering from recurrent chest pain or having a subsequent heart attack.
In effect, it means heart specialists should view all coronary arteries that are more than half-blocked as heart attacks waiting to happen, and open them up.
"We can no longer assume," Mauri says, that these bystander arteries "are innocent until proven guilty."
If the new approach has the impact some expect, it could be the next big thing in a string of advances that over the past two decades have transformed heart attack care.
Not so very long ago, heart attack had the ring of doom.
"Until 1961, patients with acute myocardial infarction — if fortunate enough to survive until they reached a hospital — were placed in beds ... far enough away from nurses' stations that their rest would not be disturbed," Elizabeth Nabel and Eugene Braunwald wrote last year. "Patients were commonly found dead in their beds ... . Indeed, the risk of death occurring in the hospital was approximately 30 percent."
In the 1970s, that grim mortality rate had been cut in half. By the 1980s, doctors had learned how to use balloon angioplasty to open blocked arteries.
Eventually heart specialists showed it was safe and often life-saving to use angioplasty in the midst of a STEMI attack. Meanwhile, developments in the use of tiny props called stents kept formerly blocked arteries open while new drugs suppressed further heart attacks.
Only nine years ago, national guidelines exhorted doctors to deliver prompt angioplasty to every STEMI patient within 90 minutes of hospital arrival.
There's still a long way to go before most at-risk patients get that standard of care. A third of patients don't get it at all, the American Heart Association says. And for those who do, only 40 percent get the culprit artery opened within the prescribed 90 minutes.
Clearly the new strategy — preventively opening up other severely narrowed arteries – won't be automatically applied overnight. But for all the progress, heart attacks are still such a big problem that even partial success could have a big payoff.