First-in-human evaluation of a novel balloon-expandable transcatheter heart valve in patients with severe symptomatic native aortic stenosis: the MyVal-1 study

Abstract

The aim of this study was to demonstrate the safety and efficacy of the next-generation balloon-expandable Myval transcatheter heart valve (THV) in an intermediate- or high-risk patient population with severe symptomatic native aortic stenosis. MyVal-1 was a first-in-human, prospective, multicentre, single-arm, open-label study. Between June 2017 and February 2018, a total of 30 patients were enrolled at 14 sites across India. Mean age was 75.5±6.7 years; 43.3% had coronary artery disease. The mean Society of Thoracic Surgeons score was 6.4±1.8% and 100% of the patients were in New York Heart Association (NYHA) functional Class II/III/IV pre-procedure. The six-minute walk test and Kansas City Cardiomyopathy Questionnaire (KCCQ) scores were recorded. After successful implantation of the Myval THV, 96.6% and 100% were in NYHA functional Class I/II at 30-day and 12-month follow-up, respectively. Outcomes of the six-minute walk test (148.0±87.4 vs 336.0±202.9 m) and KCCQ score (36.6±11.0 vs 65.9±11.4) improved from baseline to 12-month follow-up. The effective orifice area (0.6±0.2 vs 1.8±0.3 cm2, p<0.0001), mean aortic valve gradient (47.4±8.8 vs 12.0±3.3 mmHg, p<0.0001), peak aortic valve gradient (71.7±13.0 vs 20.3±5.9 mmHg, p<0.0001) and transaortic velocity (4.5±0.4 vs 2.2±0.4 m/s, p<0.0001) improved substantially from baseline to 12 months post procedure. Four all-cause mortality cases were reported up to 12 months. Moreover, there was no other moderate/severe paravalvular leak, aortic regurgitation or need for new permanent pacemaker (PPM) up to 12-month follow-up. The MyVal-1 study demonstrated the primary safety and efficacy of the Myval THV with no new PPM requirement up to 12-month follow-up. However, future trials with a larger number of patients and long-term follow-up are warranted to establish the safety and efficacy of the device.