“The one-year event rates seen compare quite favorably to other available drug-eluting stents (DES), with all showing single-digit MACE (major adverse cardiac event) and target lesion revascularization (TLR) rates,” Dr. Srihari S. Naidu, from Winthrop University Hospital, Mineola, New York, told Reuters Health.
“However, the very low rate of stent thrombosis seen, as well as our finding that early but not later interruption of DAPT (dual antiplatelet therapy) is associated with stent thrombosis, is consistent with a growing body of literature that the XIENCE stent in particular may confer a safety advantage,” he added.
The data are based on roughly 8,000 patients enrolled in a prospective, multicenter, Food and Drug Administration-required post-approval study examining the safety and effectiveness of the XIENCE V stent in real-world settings.
“It is vital to understand its behavior in a large, real-world population where a majority of implantations are for off-label indications and there is less than uniform adherence to dual anti-platelet therapy (DAPT),” Dr. Naidu said. “In this regard, the current study is the largest real-world evaluation of XIENCE, with 61% off-label use and 15% interruption of DAPT at one year (85% maintained on DAPT without interruption through one year), he explained.
Characteristic of clinical practice, one-third of patients presented with unstable angina, about 15% presented with acute MI, and diabetes, renal insufficiency and high-risk angiographic findings were common.
Clinical device success was 99.8% and clinical procedural success was 97.3%.
“We found extremely low MACE, TLR and stent thrombosis rates,” Dr. Naidu said. Incidences of definite/probable stent thrombosis, cardiac death/MI, target lesion failure, and TLR were 0.80%, 7.1%, 8.9%, and 4.3%, respectively.
“Importantly, our large sample size using a solitary DES allowed us to perform a robust evaluation of predictors of ST when the stent type is held constant,” Dr. Naidu commented.
Predictors of stent thrombosis included DAPT interruption at 30 days or less (HR 8.63; p =0.0003), renal insufficiency (HR 3.72; p=0.0009), and total stent length (HR 1.30;
“We found that only three factors predict stent thrombosis when the XIENCE stent is used, and several previously seen predictors are no longer seen, such as diabetes, bifurcation disease and reduced ejection fraction,” Dr. Naidu said.
The main limitations of the study are its observational, nonrandomized design, the lack of mandatory angiographic follow-up, and there is currently only one-year follow-up.
The study was sponsored by Abbott Vascular of Santa Clara, California. Dr. Naidu is a consultant for the company and several other authors are employees of, or have financial relationships, with the company.