PARTNER Cohort B: TAVR Remains Superior to Standard Therapy at 2 Years

SAN FRANCISCO, CALIF.—Two-year data from PARTNER Cohort B continue to support the superiority of TAVR over standard therapy for symptomatic patients with severe aortic stenosis who are not candidates for surgery.

According to Raj R. Makkar, MD, of Cedars-Sinai Medical Center in Los Angeles, TAVR with the Sapien aortic valve (Edwards Lifesciences) remained superior to standard therapy with incremental benefit from 1 to 2 years, markedly reducing the rate of all-cause mortality (see Figure 1). At 2 years, CV mortality was also higher for patients who underwent standard therapy vs. TAVR (32.1% vs. 13.2%; P<.0043). At 2 years, survival rates compared favorably to observations at 1 year.

PARTNER B Figures 1 and 2Repeat hospitalizations were also reduced with TAVR (72.5% vs. 35%; P<.0001). In fact, they were nearly halved in the TAVR group, “despite the fact that almost twice as many patients were alive in the TAVR group compared to the standard therapy group,” Makkar said. Patients who underwent TAVR spent, on average, 699 days alive and out of the hospital compared with 355 days for patients who received standard therapy.

TAVR also improved NYHA functional status and decreased the rate of class III/IV symptoms compared with standard therapy (17% vs. 64%; P<.001).

Stroke rate at 2 years remained higher in the TAVR group (see Figure 2). While there was no difference between treatment groups in the rate of all cerebrovascular events up to 1 year, researchers observed an excess stroke rate with TAVR between years 1 and 2. After 30 days, differences in stroke frequency were largely due to increased hemorrhagic strokes in TAVR patients.

Vascular events were similar between groups, although major bleeding was reported more in the TAVR group. The researchers reported no difference in the requirement for a new pacemaker between the standard therapy and TAVR groups.

According to other results, moderate or severe paravalvular aortic regurgitation in the TAVR patients did not influence 2-year survival, and there was a trend toward reduced paravalvular aortic regurgitation between 1 and 2 years. Additionally, TAVR hemodynamics by echocardiography showed durable improvements in aortic valve area and mean gradients up to 3 years after implantation.

A subgroup analysis according to surgical risk score suggested that the most pronounced benefit of TAVR is in patients without extreme clinical comorbidities, Makkar said.

“The ultimate value of TAVR in inoperable patients will depend on careful selection of patients who are not surgical candidates and yet do not have extreme comorbidities that overwhelm the benefits of TAVR and render the intervention futile,” he commented.

PARTNER randomized patients to TAVR (n=179) or standard non-surgical care (n=179) that consisted of medication and balloon aortic valvuloplasty. The 1-year results, presented at TCT 2010, demonstrated a greater likelihood of survival for inoperable patients with severe AS with TAVR and significant improvements in quality of life.

From 1 to 2 years, the researchers reported five withdrawals during the first year in the standard therapy group and 11 patients who crossed over from standard therapy. No patients were lost to follow-up.

Disclosures
  • Dr. Makkar is principal site investigator for the PARTNER trial for Edwards Lifesciences and is national principal investigator for the St. Jude Medical TAVR study. He reports receiving grant support from St. Jude Medical; consulting fees, grant support and lecture fees from Medtronic; and holds equity in Entourage Medical Technologies.

Comments