Calcium channel blockers appear to significantly reduce risk for myocardial infarction and other complications after heart surgery

Calcium channel blockers appear to significantly reduce risk for myocardial infarction and other cardiac complications following heart surgery, according to an article in the May 7th issue of the Journal of the American College of Cardiology. The meta-analysis, the first systematic review to examine use of the drug class during heart surgery, concluded that drug use significantly reduced rates of ischemia, myocardial infarction, and supraventricular tachyarrhythmias.

"I had a graduate student [lead author Duminda N. Wijeysundera, MD] who came to me and said, 'I'd like to take a look at this.' My own personal bias at the time was that he was probably not going to find anything, but he went ahead and did it, and I was sort of surprised with what he found," said W. Scott Beattie, MD, PhD, a coauthor of the study.

The current study evaluated the findings of 41 studies representing 3,327 patients. All of the studies were randomized, controlled trials of calcium channel blockers used immediately before, during, or immediately after heart surgery.

Overall, calcium channel blockers significantly reduced the risk of myocardial infarction and ischemia. Some drugs appeared to provide more benefit than others. For instance, the drugs classified as non-dihydropyridines significantly reduced supraventricular tachyarrhythmia. Although the results did not achieve statistical significance, calcium channel blockers were also associated with a trend toward lower mortality during coronary bypass surgery.

"When you actually look at all of the evidence, calcium channel blockers aren't as bad as people think they are, and in some subclasses may be potentially beneficial, with an emphasis on potential," Beattie said. "I don't think people have sat down and qualitatively looked at the evidence of cardiac surgery, and that's what this was an attempt to do."

Although Beattie said the meta-analysis results were more persuasive than he had expected, he rated the quality of the original studies as only poor to medium. Therefore, he concluded that more work is needed before recommending changes in clinical practice.

"The studies support the use of calcium antagonists, as far as they go, but we didn't do this to change management. If there is something in the meta-analysis, it really has to be taken forward into a large, randomized, controlled trial. And that's basically what we are trying to do now," he said.

The current study may help correct misperceptions about the potential risks associated with calcium channel blockers, according to editorial writer Lionel H. Opie, MD, FACC:
"Is the perception of harm correct? It largely came about in 1995 from studies when nifedipine capsules, that suddenly release large amounts of the drug into the circulation, and are now hardly ever used, were given in large doses to very seriously ill cardiac patients when it was thought that coronary spasm was the main cause of heart attacks. Rather, the nifedipine brought on heart attacks. Bad news travels, good news does not."

Opie added, "Although a major contribution, this meta-analysis does not clearly and unequivocally show that calcium channel blockers confer benefits when given in association with cardiac surgery. The authors are quite correct in emphasizing that further prospective studies are needed to determine the true effects of calcium channel blockers on outcome measures, particularly including perioperative mortality. The specific message of the present meta-analysis is quite clear: calcium channel blockers may be safer and have more benefit in cardiac surgery than often supposed."

 

 


 




DOLについて - 利用規約 -  会員規約 -  著作権 - サイトポリシー - 免責条項 - お問い合わせ
Copyright 2000-2025 by HESCO International, Ltd.