PARTNER: Benefits of TAVR Sustained Out to 3 Years

MIAMI BEACH, FLA.—Patients with symptomatic severe aortic stenosis who are not candidates for surgery continue to derive sustained clinical benefit from TAVR after 3 years, according to new data from the PARTNER trial.  The data “continue to support the role of TAVR as the standard of care for symptomatic patients with aortic stenosis who are deemed inoperable,” said E. Murat Tuzcu, MD, of Cleveland Clinic Foundation, who presented the findings at TCT 2012.

PARTNER Cohort B randomly assigned patients, all of whom had severe, symptomatic aortic stenosis and were considered inoperable, to receive either TAVR (n = 179) or standard therapy (optimal medical therapy plus balloon aortic valvuloplasty as required; n = 179). TAVR conferred a 26.8% absolute risk reduction in all-cause mortality at 36 months compared with standard therapy (see Figure).

Additionally, landmark analysis showed all-cause mortality of 40.3% in the standard treatment arm vs. 19.3% in the TAVR arm after 3 years (HR 1.9; 95% CI 1.05-3.43, log rank P=.03).

Sustained improvements

The benefits of TAVR were sustained as measured by other endpoints, including a 33.1% risk reduction for CV mortality (HR 0.41; 95% CI 0.30-0.56,  log rank P=.0001) and a 33.4% risk reduction for repeat hospitalization (HR 0.39; 95% CI 0.28-0.54,  log rank P=.0001).

Patients assigned to TAVR also demonstrated improved NYHA functional class and fewer deaths and rehospitalizations. Approximately 93% of patients assigned to standard treatment had died or were rehospitalized vs. 66.3% of patients assigned to TAVR (HR 0.46; 95% CI 0.36-0.58,  log rank P=.0001). Patients in the TAVR arm also lived longer outside of the hospital (median 944 days vs. 368 days, P=.0001) than those in the standard treatment arm.

Stroke incidence was higher in the TAVR arm (15.7% vs. 5.5%, log rank P=.0094). However, after accounting for mortality or stroke—one of the study’s primary endpoints—researchers reported a 23.4% risk reduction favoring TAVR (HR 0.60; 95% CI 0.46-0.77  log rank P<.0001).

Mean gradient was 11.3 mm Hg, similar to the 30-day gradient of 10.2 mm Hg. Valve area at 3 years was 1.5 cm2, identical to the 30-day valve area.

Although a limited number of patients had 3-year echocardiograms, “neither the frequency nor magnitude of paravalvular leak really changed appreciably over time,” Tuzcu said.

STS scores

The researchers also stratified mortality by STS score. Among patients with scores less than 5, mortality in those assigned to standard treatment was 100% compared with 33.2% for TAVR (a change of 66.8%). Mortality also was higher in the standard treatment arm in patients with scores of 5 to 14.9 (77.5% vs. 55.2%, a change of 22.3%) and 15 (86.6% vs. 65.8%, a change of 20.8%).

“Survival benefit of TAVR is dependent on the presence of comorbid illness. In contrast, without TAVR, mortality is similar irrespective of comorbid illness or the … STS score,” Tuzcu said. “These data underscore the importance of patient selection before TAVR and the need for aggressive management of illness after TAVR.”