Results from SUMMIT-MAC Announced at TCT 2025 and Published Simultaneously in JACC
SAN FRANCISCO – OCTOBER 27, 2025 – New findings from the SUMMIT-MAC study show that transcatheter mitral valve replacement (TMVR) with the Tendyne system led to successful treatment of severe mitral annular calcification (MAC) in nearly all patients, along with significant improvements in heart failure symptoms and quality of life parameters.
Findings were reported today at TCT® 2025, the annual scientific symposium of the Cardiovascular Research Foundation® (CRF®) and published simultaneously in the Journal of the American College of Cardiology (JACC). TCT is the world’s premier educational meeting specializing in interventional cardiovascular medicine.
Treatment options for patients with MAC are limited, with surgical treatment being challenging and often considered high risk. As a result, there is a critical need for safe and effective transcatheter mitral valve replacement options. The SUMMIT trial is the first nonrandomized, prospective, multicenter clinical study to assess the safety and effectiveness of the Tendyne Transcatheter Mitral Valve System in patients with significant mitral disease including a dedicated cohort with severe MAC. Features of the device include dual frame design, tether and apical pad. All enrolled patients had severe MAC, were considered high surgical risk and were approved by a case-review committee. An echocardiography core laboratory performed independent assessments of mitral disease for study inclusion and assessed all follow-up echocardiograms.
A total of 103 patients (mean age 78.0±7 years) with severe MAC and mitral valve disease (either mitral regurgitation or stenosis) underwent an attempted procedure with this transcatheter mitral valve system at 37 centers in the United States. The device was successfully implanted in all cases. The primary endpoint of freedom from all-cause mortality and heart failure hospitalization at one year was met [60.4% (50.2%, 69.2%), p=0.0002, performance goal = 43%]. One-year freedom from all-cause mortality and freedom from heart failure hospitalization rates were 79.0% and 69.9%, respectively. Bleeding was the most common severe adverse event with apical access site bleeding occurring in 5.8% of patients.
At one year, 97% of patients had mild or no mitral valve regurgitation. In addition, heart failure symptoms improved significantly with only 13% of patients having NYHA Class III symptoms compared with 73% prior to the procedure. Quality of life also improved at one year with an average 18.7 point increase in the Kansas City Cardiomyopathy Questionnaire score.
“There is a great need for safe and effective transcatheter options for patients with severe mitral annular calcification,” said Paul Sorajja, MD, Lentsch Family Endowed Chair, Service Line for Valve and Structural Heart, Banner Health. “Results from the SUMMIT-MAC pivotal trial support the Tendyne Mitral Valve System as a viable transcatheter option for these high-risk patients.”
The study was funded by Abbott.
Dr. Sorajja reported financial relationships with 4C Medical, Abbott Structural, Adona, AMX Technologies, Arcos, Boston Scientific, ConKay, Coramaze, CroiValve, Cultiv8, Edwards Lifesciences, Egg Medical, EvolutionMed, Foldax, GE Medical, Haemonetics, InQ8, LAZA, Medtronic, Mirus, Philips, Polares, Tricares, vDyne, Unorthodox Ventures, Valcare and xDot.
