Unfortunately chocolate won't help here...
WS Journal-Cardiac Pretreatment Is Challenged Studies Say Clot-Busters Before Angioplasty Raises Risk of More Heart Attacks
By SYLVIA PAGÁN WESTPHAL
February 28, 2006; Page D4
It's becoming increasingly common for heart-attack victims to be treated as soon as possible with anticlotting drugs while they await a procedure to unblock their arteries. But new studies say this practice, known as "facilitated angioplasty," doesn't benefit patients and also increases risk of subsequent heart attacks and strokes.
These findings, published earlier this month in the medical journal the Lancet, could check the growing popularity of administering the drugs before angioplasty and prompt doctors to rethink how they treat patients in the first few hours after a heart attack.
Many doctors have worked under the rationale that treating a heart-attack victim with anticlotting drugs will help open the artery while the patient waits for angioplasty. An angioplasty is a procedure in which wires are threaded through a patient's arteries to find the blockage, which is then opened up with a small balloon. However, there has been little solid evidence to justify the surging popularity of the pretreatment with drugs.
Now the Lancet studies suggest that using the drugs before angioplasty not only seems to make no difference but also can lead to more deaths and serious complications than doing angioplasty alone.
In one study, Ellen Keeley, a cardiologist from University of Texas Southwestern Medical Center, and her colleagues analyzed 17 clinical trials that compared facilitated angioplasty with angioplasty alone. Many of those clinical trials already suggested that the combination was worse, but because the studies were relatively small the individual results had been viewed as inconclusive, she said.
The pooled analysis, which involved more than 4,500 patients, looked at the two kinds of drugs commonly used in facilitated angioplasty: the so-called IIb/IIIa inhibitors, which prevent blood-clot formation, and the thrombolytics, which dissolve existing blood clots.
Using the drugs within hours of angioplasty led to more deaths, more subsequent heart attacks, more episodes of major bleeding and more strokes than angioplasty by itself, the analysis found. The differences were statistically significant.
The IIb/IIIa inhibitors didn't offer any benefit over angioplasty alone, though they were not associated with harm. The thrombolytics, on the other hand, were associated with all the major adverse events.
The results could have major implications for cardiologists and their patients. Any cardiologist aware of the new data "is saying to him or herself 'I need to rethink this,' " said Timothy Gardner, a cardiologist at the Christiana Care Hospital in Wilmington, Del., and a spokesman for the American Heart Association. "It really suggests that doctors have to totally change their practice," adds William O'Neill, chief of cardiology at the William Beaumont Hospital in Royal Oak, Mich.
About 860,000 people in the U.S. suffer from a heart attack each year. Angioplasty gained preference among cardiologists, Dr. Gardner said, because of evidence that it leads to better outcomes than treating patients with the clot-busting drugs without angioplasty.
As a result, many heart-attack patients are transferred from small hospitals to larger medical centers for an angioplasty. Faced with waiting several hours before getting the procedure, doctors assumed it would be beneficial to give these patients the anticlotting drugs while in transit.
Even patients arriving directly at hospitals with angioplasty facilities are being given the drugs if there is going to be a time delay before the procedure, Dr. Keeley said. "The natural feeling is that if you have an hour before the patient gets [the procedure] you want to do something," she said.
In the same issue of the Lancet, a separate group of researchers presented results for one of the trials analyzed in Dr. Keeley's study. The trial compared a thrombolytic drug before angioplasty with angioplasty alone. The study had to be stopped early after researchers realized that 43 of 664 patients in the combination group had died in the hospital compared with 22 of 656 in the angioplasty-alone group.
Cardiologist Gregg Stone from Columbia University Medical Center in New York called the studies' results "unequivocal" and said that, in hindsight, they aren't so surprising since the drugs increase the risk of bleeding, among other side effects. That initial bleeding could be exacerbated by a subsequent angioplasty procedure.
Dr. Stone wrote in an editorial that at this point there is "no justification to pretreat any patient" with the drugs shortly before angioplasty. "It's a bad combination," he said.
Dr. Stone said studies should now be done to find out whether, if faced with a much longer delay before angioplasty can be done, the drugs might still be helpful. Also, the possibility remains that lower doses of the drugs or different combinations of anticlotting drugs could help, Dr. Keeley and others said. |
