2-Year Outcomes Published From PARTNER 3 Trial of TAVR in Low-Risk Patients

March 1, 2021—Two-year outcomes were published from the PARTNER 3 trial, which is evaluating the safety and effectiveness of transcatheter aortic valve replacement (TAVR) with the Sapien 3 device (Edwards Lifesciences) in patients with symptomatic severe aortic stenosis who are at low surgical risk. This study determined both clinical and echocardiographic outcomes between 1 and 2 years.

Martin B. Leon, MD, et al published the PARTNER 3 findings in Journal of the American College of Cardiology (JACC; 2021;77:1149-1161). In March 2020, Michael J. Mack, MD, presented the 2-year clinical and echocardiographic outcomes from PARTNER 3 at the virtual conference of the American College of Cardiology’s Annual Scientific Session Together with World Congress of Cardiology.

As summarized in JACC, the PARTNER 3 study randomly assigned 1,000 patients (1:1) to transfemoral TAVR with the Sapien 3 valve versus surgery (mean Society of Thoracic Surgeons score, 1.9%; mean age, 73 years) with clinical and echocardiography follow-up at 30 days and at 1 and 2 years.

At 1 year, PARTNER 3 demonstrated superiority of TAVR versus surgery for the primary endpoint of death, stroke, or rehospitalization, noted the investigators. In this study, 2-year rates of the primary and several secondary endpoints (clinical, echocardiography, and quality-of-life measures) were assessed in an as-treated analysis. The primary endpoint follow-up at 2 years was available in 96.5% of patients.

In JACC, the investigators reported the following:

• The 2-year primary endpoint was significantly reduced after TAVR versus surgery (11.5% vs 17.4%; hazard ratio, 0.63; 95% CI, 0.45-0.88; P = .007)
• Differences in death and stroke favoring TAVR at 1 year were not statistically significant at 2 years (death: TAVR, 2.4.% vs surgery, 3.2%; P = .47; stroke: TAVR, 2.4% vs surgery, 3.6%; P = .28)
• Valve thrombosis at 2 years was increased after TAVR (2.6%; 13 events) compared with surgery (0.7%; three events; P = .02)
• Disease-specific health status continued to be better after TAVR versus surgery through 2 years
• Echocardiographic findings, including hemodynamic valve deterioration and bioprosthetic valve failure, were similar for TAVR and surgery at 2 years

At 2 years, the primary endpoint remained significantly lower with TAVR versus surgery. However, initial differences in death and stroke favoring TAVR were diminished, and patients who underwent TAVR had increased valve thrombosis, concluded the investigators in JACC.