Drug-coated Stents Better Than Bare Stents For High-risk Heart Patients, Pitt Study Finds

The use of drug-coated stents in patients with complex heart disease is associated with a lower rate of repeat procedures without an increased risk of death or heart attacks compared to bare metal stents, according to a study by University of Pittsburgh School of Medicine researchers.

The findings were reported in the Jan. 24 issue of the New England Journal of Medicine. The study is the largest and most detailed analysis comparing the safety and efficacy of drug-coated and bare metal stents for off-label indications, that is, when used for patients with complex disease.

“This study shows that drug-coated stents, even when used for patients with complex disease (off-label fashion), is a more effective strategy in reducing re-narrowing of the coronary arteries, without an increased risk of heart attacks or death at one year compared to bare metal stents,” said the study’s lead author, Oscar C. Marroquin, Pitt assistant professor of medicine, and director of the Center for Interventional Cardiology Research at the University of Pittsburgh Medical Center’s Cardiovascular Institute. “Furthermore, we feel that our study supports the continued use of drug-coated stents for patients with these complex heart issues.”

Stents are tiny metal mesh tubes used to treat blocked heart arteries caused by atherosclerosis—the buildup of cholesterol plaque in the arterial wall, which causes the arteries to harden and eventually become blocked. Stents, which are implanted during cardiac catheterization procedures, prop open blocked arteries. The wire mesh is used as a scaffolding device to keep an artery open. Even when the procedure is successful, the stented area can suffer re-narrowing over time caused by excess scar tissue formation that the body forms in response to the stent. It is accepted knowledge that when these stents are used in higher risk patients, the risk of re-narrowing is greater than when they are used in patients with fewer medical complications. The drug-coated stents, often preferred by cardiologists, reduce the amount of scar tissue formation, resulting in a lower likelihood of artery re-narrowing over time, compared to bare metal stents.

This study was conducted in response to an FDA call for more data on what has become common practice by cardiologists worldwide—using stents, particularly drug-eluting stents, in high-risk patients with complex conditions.

Using data from the National Heart, Lung, and Blood Institute (NHLBI) Dynamic Registry, which is managed by the Epidemiology Data Center at the University of Pittsburgh Graduate School of Public Health, Marroquin and colleagues analyzed records from 6,551 patients who were treated with either drug-coated stents or bare metal stents and whether the use was standard or off-label. Patients were followed for adverse cardiac events and death for one year after their procedures. Off-label use occurred in 55 percent of all bare metal stent patients and 49 percent of drug-coated stent patients. Compared to bare metal stent patients, drug-coated stent patients had a higher prevalence of diabetes, hypertension, renal disease, prior percutaneous coronary intervention and coronary artery bypass graft, and multi-vessel coronary artery disease. At one-year, however, there were no significant differences in the adjusted risk of death and heart attack in drug-coated stents compared to bare metal stent patients. Repeat procedures to restore blood flow also were significantly lower in drug-coated stent patients. The research findings support the use of drug-coated stents for off-label indications.

This study was funded by the NHLBI.

In addition to Marroquin, collaborators on the study included: Helen A. Vlachos, Faith Selzer, and Sheryl F. Kelsey, all from Pitt’s Graduate School of Public Health; Elizabeth M. Holper, University of Texas Southwest Medical Center, Dallas; J. Dawn Abbott and David O. Williams, both from the Rhode Island Hospital, Providence, R.I.; William D. Anderson, Joon Sup Lee, Suresh R. Mulukutla, and A. Conrad Smith, all from UPMC’s Cardiovascular Institute; Jean-Francois Tanguay, Montreal Heart Institute; Robert L. Wilensky, University of Pennsylvania, Philadelphia; and Kevin E. Kip, University of South Florida, Tampa, Fla.