A comprehensive review of the PARTNER trial

Abstract

Objective: Percutaneous transcatheter aortic valve replacement was introduced in 2002, but its effectiveness remained to be assessed.

Methods: A prospective, randomized trial (the Placement of Aortic Transcatheter Valves, or PARTNER) was designed with 2 arms: PARTNER A (n = 699) for high-risk surgical patients (Society of Thoracic Surgeons score >10%, surgeon assessed risk of mortality >15%) and PARTNER B (n = 358, patients inoperable by assessment of 2 surgeons). PARTNER A patients were divided into femoral artery access transcatheter aortic valve replacement or none (n = 207), and then randomized to open aortic valve replacement (n = 351) or device (n = 348). Inclusion criteria included valve area <0.8 cm(2), gradient >40 mm Hg or peak >64 mm Hg, and survival >1 year. The end point of the study was 1-year mortality.

Results: Thirty-day mortality for PARTNER A was 3.4% for transcatheter aortic valve replacement and 6.5% for aortic valve replacement; 1-year mortality was 24.2% and 26.8%, respectively (P = .001 for noninferiority). The respective prevalence of stroke was 3.8% and 2.1% (P = .2), although for all neurologic events, the difference between transcatheter aortic valve replacement and aortic valve replacement was significant (P = .04), including 4.6% for femoral artery access transcatheter aortic valve replacement versus 1.4% for open aortic valve replacement (P = .05). For PARTNER B--transcatheter aortic valve replacement versus medical treatment-30-day mortality was 5.0% versus 2.8% (P = .41), and at 1 year, mortality was 30.7% versus 50.7% (P < .001), respectively. Hospitalization cost of transcatheter aortic valve replacement for PARTNER B was $78,542, or $50,200 per year of life gained. Analysis of PARTNER A strokes showed that hazard with transcatheter aortic valve replacement peaked early, but thereafter remained constant in relation to aortic valve replacement. Two-year PARTNER A data showed paravalvular regurgitation was associated with increased mortality, even when mild (P < .001). Continued access to transapical transcatheter aortic valve replacement (n = 853) showed a mortality of 8.2% and decline in strokes to 2.0%. Of the 1801 Cleveland Clinic patients reviewed to December 2010, 214 (12%) underwent transcatheter aortic valve replacement with a mortality of 1%; in 2011, 105 underwent transcatheter aortic valve replacement: 34 transapical aortic valve replacement, with no deaths, and 71 femoral artery access aortic valve replacement with 1 death.

Conclusions: The PARTNER A and B trials showed that survival has been remarkably good, but stroke and perivalvular leakage require further device development.