New Version of Sapien Transcatheter Aortic Valve Replacement System Produces Improved Outcomes Compared to Original Version

Results from the PARTNER II trial show improvements in 30-day mortality and stroke rates in patients with aortic stenosis who are not surgical candidates who were treated using a newer version of the Sapien transcatheter aortic valve replacement system.

Late-breaking results from the Placement of AoRTic TraNscathetER Valves (PARTNER II) trial were presented yesterday at ACC.13, the 62nd Annual Scientific Session & Expo of the American College of Cardiology, by Martin Leon, MD, Director, Center for Interventional Vascular Therapy, Columbia University Medical Center and New York-Presbyterian Hospital. Leon said the goal of the trial was to compare the safety and efficacy of transcatheter aortic valve replacement (TAVR) with the balloon-expandable Sapien XT device versus the first-generation Sapien device. Although US doctors are just learning about the device, it’s used clinically in many other countries.

This randomized, parallel, evolutionary study screened 560 patients in 28 sites over one year. Patients were inoperable for surgical aortic valve replacement (AVR), and had severe aortic stenosis. Exclusion criteria included: aortic annulus less than 18 mm or greater than 25 mm, minimum iliac-femoral diameter less than 7 mm, left ventricular dysfunction less than 20%, need for coronary revascularization, serum creatinine more than 3 mg/dl, acute myocardial infarction within the last month, stroke/TIA within the last six months, and hemodynamic instability.

Patients were randomized to transfemoral TAVR with Sapien XT (284) versus the first-generation Sapien device (276). The mean age of patients in this cohort was 84 years. Nearly half of participants were women. In this study, 11% of patients had previous stroke, 31% had peripheral arterial disease, 36% had diabetes, 30% had chronic obstructive pulmonary disease, 35% had a history of cancer, 37% had prior atrial fibrillation, and 59% met inoperability criteria based on frailty.

Aortic valve area at one year was 1.4 cm2 with the Sapien XT, versus 1.5 cm2 with the Sapien. Moderate to severe aortic regurgitation at one year was observed in 29% of the Sapien XT group versus 21% of the Sapien group (P= 0.20).

The primary endpoint of the study was a composite of all-cause mortality, disabling stroke, or hospitalization at one year (noninferiority design). All-cause death, stroke, or hospitalization at one year occurred in 33.9% of the Sapien XT group versus 34.7% of the original Sapien group, with no significant differences in mortality (P=0.0034). All-cause mortality at one year was 22.5% for Sapien XT versus 23.7% for the original device (P = 0.71). Disabling stroke at one year was 4.5% versus 4.6% (P = 0.93), respectively. Hospitalization at one year was 17.4% versus 19.0% (P = 0.69), respectively.

There was an increase in paravalvular regurgitation, and this offset contributed to differences between the two devices, warranting more critical examination. The study demonstrated clinically meaningful secondary endpoints, justifying this device compared to the current Sapien device used in the US.

The Sapien XT (whose 40% smaller size facilitated entry) appeared to fulfill expectations, with shorter procedures, and reduced time under anesthesia. Hemodynamics improved, and need for a second valve was significantly reduced, as were the number of aborted procedures (due to inability to advance device or cross valve), and vascular complications.

Patients with inoperable aortic stenosis generally have very high mortality, driven by procedural issues and underlying disease states, and by the time of procedure survival is dictated by comorbidities. Bleeding complications become especially important in these elderly, frail populations. This device corrects a fundamental mortality problem of aortic stenosis, and is procedurally easier for surgeons.

The study showed multiple improvements in TAVR with Sapien XT versus the first-generation Sapien device. Sapien XT significantly reduced vascular complications, with similar mortality and stroke rate at 30 days. The approval of the Sapien XT device for clinical use is eagerly awaited.