The Myval Transcatheter Heart Valve System for the Treatment of Severe Aortic Stenosis - Current Evidence and Future Directions

Case report: A complex case of valve-in-valve TAVI and left bundle branch pacing for severe aortic regurgitation with partially corrected type A aortic dissection and low ejection fraction

Background

Aortic regurgitation is a major concern following transcatheter aortic valve implantation (TAVI), as even low-grade regurgitation is associated with increased mortality. This is of particular concern to patients with pre-existing aortic disease who are at increased risk of TAVI valve slippage. Furthermore, conduction system disturbances after TAVI, namely left bundle branch block (LBBB), may have an additional detrimental effect on cardiac function.

Case presentation

This report documents a successful treatment strategy in a frail patient with a bicuspid aortic valve and aortic disease after valve-sparing surgical repair in 1998, who subsequently developed aortic stenosis and underwent TAVI with an Evolut R self-expanding aortic valve. The progression of aortic disease, aortic root dilatation, and leaflet degeneration over the following years caused aortic regurgitation of the self-expanding aortic valve, resulting in left ventricular dilatation and heart failure along with LBBB and left ventricular (LV) mechanical dyssynchrony. Diagnostic workup of the patient showed persistence of the aneurysm distal to the graft with a dissection spanning the ascending aorta, arch, and terminating proximal to the aortic isthmus. After consideration by the cardiac team, a balloon-expandable valve was chosen for a valve-in-valve (ViV) procedure to provide sufficient radial force to expand the existing valve and correct the regurgitation. Due to the anatomy, a J-wire and pigtail catheter were successfully used for a safe approach and placement of the valve. Following the procedure, intermittent complete atrioventricular block was observed in addition to the pre-existing left bundle branch block, necessitating resynchronization pacing. Due to anatomical considerations, ease of placement, and the expected good level of resynchronization due to the proximal block, we opted for left bundle branch pacing, which showed improvement in left ventricular dyssynchrony and LV function at follow-up.

Conclusion

Valve-in-valve implantation of a balloon-expandable Myval TAVI device to treat aortic regurgitation caused by slippage and right leaflet disfunction of slef valve is feasible in challenging anatomical scenarios. Left bundle branch pacing is a viable alternative to correct mechanical dyssynchrony in complex patients with LBBB and anatomical challenges necessitating resynchronization.

Myval: A Novel Transcatheter Heart Valve for the Treatment of Severe Aortic Stenosis

Transcatheter aortic valve implantation (TAVI) performed using femoral arterial access is now a guideline recommended treatment for severe calcific aortic stenosis (AS) in elderly patients. Technological advancements and procedural refinements have focused on making TAVI simpler, safer, more effective and durable. Myval (Meril Lifesciences) is a new generation balloon-expandable transcatheter heart valve (THV) developed in India that possesses novel features to improve deliverability and aid precise deployment. Following the first-in-human study, Myval was approved in India for commercial implantation in October 2018 and was subsequently given a CE mark in April 2019. This article reviews the science, technology and up-to-date clinical evidence for the Myval THV.

First experiences with Myval Transcatheter Heart Valve System in the treatment of severe pulmonary regurgitation in native right ventricular outflow tract and conduit dysfunction

The rate of morbidity and mortality related to pulmonary regurgitation and pulmonary stenosis are big concerns after the surgery for CHD. Percutaneous pulmonary valve implantation has been established as a less invasive technique compared to surgery with promising results according to long-term follow-up of the patients. There are only two approved valve options for percutaneous pulmonary valve implantation until now, which are Melody (Medtronic, Minneapolis, Minn, USA) and Sapien (Edwards Lifesciences, Irvine, Ca, USA). Both valves have limitations and do not cover entire patient population. Therefore, the cardiologists need more options to improve outcomes with fewer complications in a such promising area. Herein, we present a case series applying for pulmonary position in conduits and native right ventricular outflow tract of a new transcatheter valve system Myval ® which is designed for transcatheter aortic valve implantation procedures. This is the first patient series in which the use of Myvalv in dysfunctional right ventricular outflow tracts is described, after surgical repair of CHD.