PARTNER Trial's Cohort A Published for Edwards Sapien Valve

June 5, 2011—Craig R. Smith, MD, et al published the results from the PARTNER trial of transcatheter aortic valve replacement (TAVR) in high-risk surgical patients (cohort A) with severe aortic stenosis. Sponsored by Edwards Lifesciences Corporation (Irvine, CA), the PARTNER trial is the pivotal clinical study of the Edwards Sapien transcatheter aortic valve in high-risk surgical patients (cohort A) and high-risk inoperable patients (cohort B) with severe aortic stenosis. In September 2010, Cardiac Interventions Today reported that the cohort B data was published in The New England Journal of Medicine (2010;363:1597–1607).

The cohort A study results are available online ahead of print in The New England Journal of Medicine. As reported by Cardiac Interventions Today, Dr. Smith first presented the data on April 3, 2011, at the American College of Cardiology's 60th annual scientific session in New Orleans.

According to the investigators, TAVR has been shown to reduce mortality among high-risk patients with aortic stenosis who are not candidates for surgical replacement. However, the two procedures have not been compared in a randomized trial involving high-risk patients who are still candidates for surgical replacement.

As detailed in The New England Journal of Medicine, the investigators at 25 centers randomly assigned 699 high-risk patients with severe aortic stenosis to undergo either TAVR with a balloon-expandable bovine pericardial valve (the Edwards Sapien valve delivered via either a transfemoral or a transapical approach) or surgical replacement. The primary endpoint was death from any cause at 1 year. The primary hypothesis was that TAVR is not inferior to surgical replacement.

The investigators reported that rates of death from any cause were 3.4% in the TAVR group and 6.5% in the surgical group at 30 days (P = .07) and 24.2% and 26.8%, respectively, at 1 year (P = .44), a reduction of 2.6 percentage points in the TAVR group (upper limit of the 95% confidence interval, 3 percentage points; predefined margin, 7.5 percentage points; P = .001 for noninferiority). The rates of major stroke were 3.8% in the TAVR group and 2.1% in the surgical group at 30 days (P = .2) and 5.1% and 2.4%, respectively, at 1 year (P = .07). At 30 days, major vascular complications were significantly more frequent with TAVR (11% vs 3.2%; P < .001); adverse events that were more frequent after surgical replacement included major bleeding (9.3% vs 19.5%; P < .001) and new-onset atrial fibrillation (8.6% vs 16%; P = .006). More patients undergoing TAVR had an improvement in symptoms at 30 days, but by 1 year, there was not a significant between-group difference.

The PARTNER trial investigators concluded that in high-risk patients with severe aortic stenosis, transcatheter and surgical procedures for aortic valve replacement were associated with similar rates of survival at 1 year, although there were important differences in periprocedural risks.

In an accompanying editorial, Hartzell V. Schaff, MD, discusses the findings of the study, the pros and cons of TAVR as a future treatment option, and the need for further research and development of techniques and adjunctive devices such as embolic protection.