Systolic anterior motion of a transatrial transcatheter mitral valve replacement causing left ventricular outflow tract obstruction

Transatrial transcatheter mitral valve replacement is a hybrid strategy involving placing the patient on cardiopulmonary bypass and direct implantation of a transcatheter valve in a calcified annulus for mitral annular calcification. We report a rare phenomenon of systolic anterior motion of the leaflets of a transcatheter heart valve prosthesis used for mitral valve replacement causing left ventricular outflow tract obstruction. Although reported in transcatheter mitral valve replacement, we believe this is the first report of left ventricular outflow tract obstruction after transatrial mitral valve replacement and discuss the pre-disposing risk factors.

5-Year Prospective Evaluation of Mitral Valve-in-Valve, Valve-in-Ring, and Valve-in-MAC Outcomes: MITRAL Trial Final Results

BACKGROUND

The MITRAL (Mitral Implantation of Transcatheter Valves) trial is the first prospective trial to evaluate the safety and feasibility of balloon-expandable aortic transcatheter heart valves in patients with failed surgical bioprostheses or annuloplasty rings and severe mitral annular calcification treated with mitral valve-in-valve (MViV), valve-in-ring (MViR), or valve-in-mitral annular calcification (ViMAC).

OBJECTIVES

The aim of this study was to evaluate 5-year outcomes among these patients.

METHODS

A multicenter prospective study was conducted among patients at high surgical risk at 13 U.S. sites. Patients underwent MViV (n = 30), MViR (n = 30), or ViMAC (n = 31) and were followed annually for 5 years. Kansas City Cardiomyopathy Questionnaire scores were obtained at baseline and follow-up visits. Echocardiograms were analyzed at independent core laboratories.

RESULTS

A total of 91 patients underwent transcatheter mitral valve replacement (February 2015 to December 2017). The mean age was 74.3 ± 8.9 years. At 5-year follow-up, the lowest all-cause mortality was observed in the MViV group (21.4%), 94.7% of patients were in NYHA functional class I or II, and the mean mitral gradient was 6.6 ± 2.5 mm Hg. The MViR and ViMAC groups had higher all-cause mortality (65.5% and 67.9%), most survivors were in NYHA functional classes I and II (50% and 55.6%), and mean mitral gradients remained stable (5.8 ± 0.1 and 6.7 ± 2.5 mm Hg). Significant improvements in Kansas City Cardiomyopathy Questionnaire scores were observed when all 3 arms were pooled.

CONCLUSIONS

MViV, MViR, and ViMAC procedures were associated with sustained improvement of heart failure symptoms and quality of life among survivors at 5 years. Transcatheter heart valve function remained stable in all 3 groups. Patients treated with MViV had excellent survival at 5 years, whereas survival was lower in the MViR and ViMAC groups, consistent with underlying disease severity. Patients with more residual mitral regurgitation had higher mortality.

Contemporary Review of Transcatheter Mitral Valve Interventions for Mitral Regurgitation

Mitral regurgitation (MR) is the most common form of valvular heart disease in the United States, and there are established guidelines for indications for requiring mitral valve surgeries. However, there is an unmet clinical need for a subset of high-risk MR patients, especially those with advanced age, heart failure and/or secondary MR. Following the successes of transcatheter aortic valve replacements, significant advances have occurred over the last decade in transcatheter mitral valve interventions in order to manage these patients in both clinical practice and trials. The three main types of these interventions include a transcatheter edge-to-edge repair, percutaneous mitral annuloplasty (both direct and indirect) and transcatheter mitral valve replacement (including when applied to a prior prosthetic valve, annuloplasty ring and mitral annuloplasty ring). This review aims to discuss the contemporary techniques, evidence, indications, multimodality imaging evaluations and outcomes of the various transcatheter mitral valve interventions.