SUMMIT-MAC Evaluates Abbott’s Tendyne TMVR System for Severe Mitral Annular Calcification

October 27, 2025—New findings from the SUMMIT-MAC study show that transcatheter mitral valve replacement (TMVR) with the Tendyne system (Abbott) led to successful treatment of severe mitral annular calcification (MAC) in approximately all patients, along with significant improvements in heart failure symptoms and quality-of-life parameters.

The SUMMIT-MAC findings were reported at the TCT 2025 scientific symposium and published simultaneously by Paul Sorajja, MD, et al in the Journal of the American College of Cardiology.

“There is a great need for safe and effective transcatheter options for patients with severe mitral annular calcification,” commented Dr. Sorajja in the TCT press release. “Results from the SUMMIT-MAC pivotal trial support the Tendyne mitral valve system as a viable transcatheter option for these high-risk patients.”

According to TCT, the SUMMIT trial is a nonrandomized, prospective, multicenter clinical study that assessed the safety and effectiveness of the Tendyne TMVR system in patients with significant mitral disease and included a dedicated cohort with severe MAC.

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.

As summarized in the TCT press release, the study included 103 patients (mean age, 78.0 ± 7 years) with severe MAC and mitral valve disease (either mitral regurgitation or stenosis) who underwent an attempted procedure with the Tendyne TMVR system at 37 centers in the United States, and the device was successfully implanted in all cases.

The 1-year findings presented at TCT included the following:

• Freedom from all-cause mortality and heart failure hospitalization—the primary endpoint—was met at 60.4% (50.2%, 69.2%; P = .0002) with a performance goal of 43%.
• Freedom from all-cause mortality was 79%.
• Freedom from heart failure hospitalization was 69.9%.
• The most common severe adverse event was bleeding, with apical access site bleeding in 5.8% of patients.
• 97% of patients had mild or no mitral valve regurgitation.
• Heart failure symptoms improved significantly with only 13% of patients having New York Heart Association class III symptoms compared with 73% before the procedure.
• Quality of life improved with an average 18.7-point increase in the Kansas City Cardiomyopathy Questionnaire score.