NEW YORK (Reuters Health) – Drug-eluting stents (DES) seem to be safer and more effective than bare-metal stents in saphenous vein grafts (SVG), according to a systematic review and meta-analysis of relevant studies.
The analysis, by cardiologists at the Gill Heart Institute, University of Kentucky in Lexington, found lower rates of repeat procedures and major adverse cardiac events with DES compared BMS. “Reassuringly,” these benefits do not come with any compromise in safety, they say.
“Based on this meta-analysis, and another one with similar conclusions published this month in Circulation: Cardiovascular Interventions, we believe that our first choice in SVG intervention should be DES,” senior author Dr. Khaled M. Ziada told Reuters Health by e-mail.
DES are not approved for SVG lesions, but they’re widely used in this setting nonetheless. Several small studies have shown a benefit for DES in reducing need for repeat procedures, Dr. Ziada said, but others showed no such effect and some even showed some danger in using DES.
“We hypothesized that the reason for this inconsistency is due to the small number of patients in each study, which makes these studies susceptible to chance findings,” Dr. Ziada said. “A meta-analysis addresses these concerns to a large degree by attempting to compile a larger number of patients to avoid these issues, as long as the patients compiled together are homogeneous.”
As reported in the December Journal of the American College of Cardiology: Cardiovascular Interventions, Dr. Ziada and colleagues identified four randomized controlled trials and 19 cohort studies comparing BMS with DES in SVG interventions in a total of 5,324 patients. From these studies, they abstracted clinical end point data and analyzed it in aggregate and in subgroup analyses with a random-effects model.
They found that use of a DES was associated with a 25% lower odds of dying (odds ratio 0.75), about a 43% lower risk of target lesion or target vessel revascularization (odds ratios 0.57 and 0.56, respectively), and a 39% lower risk of major adverse cardiac events (odds ratio 0.61).
DES use also led to a significant absolute risk reduction in target lesion revascularization, target vessel revascularization and major adverse cardiac events of minus 0.07, 0.10, and 0.12, respectively.
Importantly, the clinicians report in their article, there was no significant between-group difference in recurrent myocardial infarction or stent thrombosis (odds ratios 0.99 and 0.78).
“We show that there is no danger in using DES; in fact, DES is associated with a very significant reduction in target vessel revascularization. We did not see the signal for harm with DES seen in an earlier smaller study and can thus suggest that was a chance finding,” Dr. Ziada told Reuters Health.
“Our conclusions are consistent with most of the published series, particularly the randomized trials and the higher-quality smaller studies,” Dr. Ziada said.
Despite its reassuring findings, this meta-analysis is no substitute for a well-designed appropriately powered randomized trial to compare long-term outcomes of DES vs BMS in SVG interventions, the study team notes in their report.
“A VA cooperative trial is about to launch next month to address this question once and for all, hopefully,” Dr. Ziada said. The “DIVA” trial, he explained, will randomize patients getting SVG intervention to DES or BMS and follow them for an extended period of time.
“The study is well powered and should be able to give us a definitive answer,” Dr. Ziada said.
J Am Coll Cardiol Intv 2010;3:1262-1273
