Drug-eluting stents show no increased risk of mortality, while decreasing the need for repeat procedures to unblock coronary arteries, according to a report published in the Journal of the American Medical Association by Dartmouth Medical School professors David Malenka and Aaron Kaplan.
There has been growing concern that drug-eluting stents carry an increased risk of stent thrombosis, or a blood clot near the stent, in comparison to bare-metal stents. This is a cause for concern because, although rare, stent thrombosis is associated with a high risk of myocardial infarction.
Stents are small mesh tubes inserted into arteries to help keep them open. Drug-eluting stents (DES) were developed to reduce the incidence of restenosis, or re-narrowing of the coronary arteries, that often creates the need for additional procedures to correct the problem.
Malenka and Kaplan used data on 38,917 Medicare patients receiving non-emergency coronary stenting immediately before the introduction of DES (October 2002 through March 2003) and on 28,086 similar patients who received coronary stents shortly after the introduction of the technology (September though December 2003), according to their report.
This investigation examined the rates of survival, myocardial infarction, and repeat procedures to unblock coronary arteries between bare-metal stents (BMS) and drug-eluting stents, specifically cipher stents. The study found a significant decrease in the number of repeat procedures to unblock coronary arteries in the patient group when DES were available compared with BMS-receiving patients (19.0%, 22.8%, p<0.001). Also, the researchers found that there was no significant difference in survival or myocardial infarction rates after hazard adjustment.
“Although such an analysis will not answer the question of what is the true rate of stent thrombosis with drug-eluting stent vs. the rate with bare-metal stent, it does address the important question of whether, on-average, the population of stented patients is being helped or hurt by the widespread use of this technology,” Malenka and Kaplan report.
Further Reading:
Dartmouth Medical School article
Malenka et al., JAMA, June 2008.