PARTNER Cohort A Data Evaluated for Impact on Left Ventricular Dysfunction

December 20, 2013—In Circulation: Cardiovascular Interventions, Sammy Elmariah, MD, et al published findings from a study of the PARTNER (Cohort A) trial that aimed to evaluate the effect of left ventricular (LV) dysfunction on clinical outcomes after transcatheter and surgical aortic valve replacement (TAVR and SAVR, respectively) and the impact of aortic valve replacement technique on LV function (2013;6:604–614).

The background of the study is that the PARTNER (Cohort A) trial demonstrated similar survival after TAVR and SAVR in high-risk patients with symptomatic, severe aortic stenosis.

As summarized in Circulation: Cardiovascular Interventions, the PARTNER trial randomized high-risk patients with severe aortic stenosis to TAVR or SAVR. Patients were stratified by the presence of LV ejection fraction (LVEF) < 50%. All-cause mortality was similar for TAVR and SAVR at 30 days and 1 year regardless of baseline LV function and valve replacement technique.

At 1 year, in patients with LV dysfunction, mean LVEF increased from 35.7 ± 8.5% to 48.6 ± 11.3% (P < .0001) after TAVR and from 38 ± 8% to 50.1 ± 10.8% after SAVR (P < .0001). Higher baseline LVEF (odds ratio, 0.9; 95% confidence interval [CI], 0.86 to 0.95; P < .0001) and previous permanent pacemaker (odds ratio, 0.34; 95% CI, 0.15 to 0.81) were independently associated with reduced likelihood of ≥ 10% absolute LVEF improvement by 30 days; higher mean aortic valve gradient was associated with increased odds of LVEF improvement (odds ratio, 1.04 per 1 mm Hg; 95% CI, 1.01 to 1.08). Failure to improve LVEF by 30 days was associated with adverse 1-year outcomes after TAVR but not SAVR.

The investigators concluded that in high-risk patients with severe aortic stenosis and LV dysfunction, mortality rates and LV functional recovery were comparable between valve replacement techniques. TAVR is a feasible alternative for patients with symptomatic severe aortic stenosis and LV dysfunction who are at high risk for SAVR, stated the investigators in Circulation: Cardiovascular Interventions.