One-year death rate nearly halved in Dutch study
THURSDAY, June 5 (HealthDay News) -- Vacuuming out loose pieces of clots before artery-opening treatment of a heart attack reduced the one-year death rate by nearly half in a Dutch trial, a result that cardiologists said could change medical practice.
The latest data on the trial of a technique called thrombus aspiration showed that just 19 of 535 heart attack victims -- 3.6 percent -- given the treatment died within a year, compared to 36 deaths among the 536 people -- 6.7 percent -- given conventional treatment.
Death or a second heart attack occurred in 5.6 percent of the aspiration group and 9.9 percent of those given conventional treatment, the researchers reported.
"The point that thrombus aspiration has a role is definitely made," said study lead author Dr. Felix Zijlstra, head of the department of acute cardiology at the University Medical Centre Groningen.
"Nevertheless, we will continue to follow these patients for many years and define the predictors of long-term, five-year outcome," he added.
The findings are in the June 7 issue of The Lancet.
All 1,071 people in the trial were given emergency treatment called percutaneous coronary intervention (PCI) for the kind of heart attack formally called ST-elevation myocardial infarction, a term that refers to the pattern traced out by an electrocardiogram. The usual treatment is insertion of a balloon-tipped catheter to reopen the blocked coronary artery. In this trial, a device was also used to suck out clot particles before insertion of the catheter.
Use of the technique is starting to spread, Zijlstra said. "Several companies report, in personal communications, increasing sales of aspiration devices," he said.
The technique is not difficult to master, Zijlstra said. "Experienced interventional cardiologists can easily implement thrombus aspiration in the PCI procedure," he said. "It is not more demanding than other intracoronary manipulations."
Use of the aspiration technique is being expanded to other cardiac emergencies, Zijlstra said.
"We are currently enrolling patients in a trial that studies the role of aspiration in patients with non-ST elevation acute coronary syndromes," he said. "Results of a pilot study have been accepted for publication but are not yet publicly available."
Dr. Howard Cohen, director of cardiac intervention at Lenox Hill Hospital in New York City, said the new study shows that "removing thrombus [blood clots] markedly improves short- and long-term outcomes." He added, "I use it all the time."
Some earlier studies showed conflicting results, Cohen said, but the new report clarifies the situation. "Based on this information, I think this will change the guidelines in terms of treatment of thrombus in acute myocardial infarction," he said.
Removing blood clot fragments from the heart blood vessel is important because "thrombus in an artery is a marker for poor outcome," Cohen said. "The nice thing about this technique is that it is very simple and widely applicable, and outcomes are significantly improved," he said.
Dr. Manesh R. Patel, an assistant professor of medicine in the division of cardiology at Duke University Medical Center, called the new findings "promising."
"I would expect a higher use of aspiration, but whether it will be in all patients, I'm not sure," he said.
At present, Duke cardiologists use aspiration in heart attack treatment when there is a completely blocked artery and "a large thrombus burden that is visible," Patel said. The newly reported results probably will expand the technique's use, he said.
Learn more about treatment of heart attacks from the American Heart Association.
SOURCES: Felix Zijlstra, M.D., head of acute cardiology, University Medical Centre Groningen, the Netherlands; Howard Cohen, M.D., director of cardiac intervention, Lenox Hill Hospital, New York City; Manesh R. Patel, M.D., assistant professor of medicine, division of cardiology, Duke University Medical Center, Durham, N.C.; June 7, 2008, The Lancet
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