Cleveland Clinic Presents Largest Study To Date Clarifying The Risk Related To Surgery Performed After Drug-Eluting Stents
While an increased risk of stent thrombosis, heart attack and death with surgeries performed in patients with drug- eluting stents has been suspected on the basis of anecdotes, until now, no large study had quantified that risk.
The study presented today at the American Heart Association’s 27th Annual Scientific Session comprised 543 patients at Cleveland Clinic who underwent surgeries between April 2003 and Apr. 1, 2007. Of the surgeries, 77% were non-cardiac and 23% were cardiac surgery. Patients who underwent surgical procedures prior to receiving drug-eluting stents and those who underwent outpatient procedures were excluded from the study.
“Our findings show that the risk of blood clot formation, heart attack and death is highest among patients who undergo major surgery within 30 days of receiving drug-eluting stents, but the risk may persist as far out as three years,” said Stephen G. Ellis, M.D., Director of the Cardiac Catheterization Lab at Cleveland Clinic and the study’s Senior Investigator. “This suggests that it is critical for patients to share their long-term medical plans with physicians because not even therapies like aspirin and clopidogrel appear to protect these patients.”
Results of the study “Characterization of Perioperative Risk Associated With Drug-Eluting Stent” were presented by Saif Anwaruddin, M.D., a Cleveland Clinic Cardiology Fellow. The study builds on previous research which found that non-cardiac surgery shortly after the implantation of bare-metal stents increased the risk of blood clot formation or thrombosis, but that risk dissipated after four to six weeks.
In this study, the patient data base was examined for patients who suffered blood clots, heart attack or death within 30 days of undergoing a non-cardiac surgery following the implantation of a drug-eluting stent. Results show that of this patient population, the risk of stent thrombosis was highest when the surgery was performed within 30 days of the implantation of a drug-eluting stent. Of patients who experienced thrombosis, 72% died. Similarly, the study showed that being on aspirin and/or clopidogrel at this time was not sufficiently protective.
The study was limited in that it involved retrospective data, a single center’s experience and a low number of absolute stent thrombosis events or blood clot formation, said Study Co-investigator Arman Askari, M.D. However, the findings warrant additional research to direct physicians with regards to using drug-eluting stents among patients planning to undergo surgical procedures in the near-term and beyond.
Cleveland Clinic, located in Cleveland, Ohio, is a not-for-profit multispecialty academic medical center that integrates clinical and hospital care with research and education. Cleveland Clinic was founded in 1921 by four renowned physicians with a vision of providing outstanding patient care based upon the principles of cooperation, compassion and innovation. U.S. News & World Report consistently names Cleveland Clinic as one of the nation’s best hospitals in its annual “America’s Best Hospitals” survey. Approximately 1,800 full-time salaried physicians and researchers at Cleveland Clinic and Cleveland Clinic Florida represent more than 100 medical specialties and subspecialties. In 2006, there were 3.1 million outpatient visits to Cleveland Clinic. Patients came for treatment from every state and from more than 80 countries. There were more than 53,000 hospital admissions to Cleveland Clinic in 2006. Cleveland Clinic’s Web site address is www.clevelandclinic.org.
