The PARTNER II trial [NCT01314313] enrolled high-risk operable, inoperable, and intermediate-risk operable patients with symptomatic severe aortic stenosis (AS) to receive the most recently available transcatheter heart valve (THV). Both patient groups experienced lower-than-expected mortality and stroke outcomes, with low rates of adverse events (AEs) and paravalvular leak.

Since their introduction in 2003, balloon-expandable THVs have continued to evolve. The current SAPIEN 3 (S3) valve, available since 2013, is size 14 French and has several modified features in the valve and its delivery system. To investigate this new iteration of transcatheter aortic valve replacement, the PARTNER II trial was designed to evaluate safety and efficacy outcomes for the S3 THV system for use in inoperable, high-risk, and intermediate-risk patients.

Susheel Kodali, MD, Columbia University Medical Center, New York, New York, USA, presented an as-treated analysis of 30-day data from the PARTNER II trial, which consisted of 2 single-arm, nonrandomized, historical-controlled studies, and enrolled a combined 1659 patients with symptomatic severe AS: 1076 intermediate-risk operable (S3i), and 583 high-risk operable or inoperable (S3HR). All patients received the S3 THV. Exclusion criteria were stroke or transient ischemic attack within 6 months, myocardial infarction within 1 month, untreated significant coronary artery disease, upper gastrointestinal bleed within 3 months, renal failure, prior prosthetic valve, left ventricular ejection fraction < 20%, and estimated life expectancy < 24 months. S3HR patients were enrolled at 29 sites across the United States, and S3i patients were enrolled at 51 US sites.

In both patient groups, 99.5% of patients completed follow-up visits 30 days after receiving the S3 THV. Baseline characteristics reflect the high-risk nature of both groups; the average ages were > 80 years, with average Society of Thoracic Surgeons (STS) surgery risk scores at 5.3% for S3i patients and 8.6% for S3HR patients. Between-group differences in baseline characteristics and comorbidities also reflected the risk status of each group.

Thirty-day results for the as-treated S3i and S3HR patients are summarized in Table 1. The STS risk scores were 5.3% for the S3i group and 8.6% for the S3HR group.

AEs were low for these populations, and the procedure was considered well tolerated.

Compared to previous studies, at 30-day follow-up, the S3 THV resulted in the lowest rates of all-cause mortality, stroke, and paravalvular leak of all available balloon-expandable THVs. Dr Kodali went over the excellent clinical outcomes seen in both the intermediate-risk and high-risk/inoperable groups, and cited these results as evidence that the S3 THV is an attractive alternative to surgery for all patients with AS.