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.

Favorable Atrial Remodeling After Percutaneous Pulmonary Valve Implantation and Its Association With Changes in Exercise Capacity and Right Ventricular Function

Background Right atrial (RA) dilatation and impaired right ventricular (RV) filling are common in patients with RV outflow tract dysfunction. We aimed to study potential correlations between atrial function with clinically relevant hemodynamic parameters and to assess the predictive impact of atrial performance on the recovery of exercise capacity and RV pump function after percutaneous pulmonary valve implantation (PPVI). Methods and Results Altogether, 105 patients with right ventricular outflow tract dysfunction (median age at PPVI, 19.2 years; range, 6.2–53.4 years) who underwent cardiac magnetic resonance imaging before and 6 months after PPVI were included. RA and left atrial maximal and minimal volumes as well as atrial passive and active emptying function were assessed from axial cine slices. RA emptying function was inversely related to invasive RV end‐diastolic pressure, and RA passive emptying correlated significantly with peak oxygen uptake. After PPVI, a significant decrease in RA minimum volume was observed, whereas RA passive emptying function improved, and RA active emptying function decreased significantly. Patients with predominant right ventricular outflow tract stenosis showed more favorable changes in RA active and left atrial passive emptying than those with primary volume overload. None of the RA and left atrial emptying parameters was predictive for recovery of peak oxygen uptake or RV ejection fraction. Conclusions In patients with right ventricular outflow tract dysfunction, impaired RA emptying assessed by cardiac magnetic resonance imaging was associated with increased RV filling pressures and lower exercise capacity. PPVI leads to a reduction in RA size and improved passive RA emptying function. However, RA function was not associated with improved exercise performance and RV pump function.

Coronary Artery Anomalies and Their Impact on the Feasibility of Percutaneous Pulmonary Valve Implantation

One of the major obstacles preventing successful percutaneous pulmonary valve implantation (PPVI) is related to the close proximity of coronary artery branches to the expected landing zone. The aim of this study was to assess the frequency of coronary artery anomalies (CAAs) especially those associated with major coronary branches crossing the right ventricular outflow tract (RVOT) and to describe their relevance for the feasibility of percutaneous pulmonary valve implantation (PPVI). In our retrospective single-center study 90 patients were evaluated who underwent invasive testing for PPVI in our institution from 1/2010 to 1/2020. CAAs were identified in seven patients (8%) associated with major branches crossing the RVOT due to origin of the left anterior descending (LAD) or a single coronary artery from the right aortic sinus. In 5/7 patients with CAAs balloon testing of the RVOT and selective coronary angiographies revealed a sufficiently large landing zone distal to the coronary artery branch. While unfavorable RVOT dimensions prevented PPVI in one, PPVI was performed successfully in the remaining four patients. The relatively short landing zone required application of the “folded” melody technique in two patients. All patients are doing well (mean follow-up 3 years). CAAs associated with major coronary branches crossing the RVOT can be expected in about 8% of patients who are potential candidates for PPVI. Since the LAD crossed the RVOT below the plane of the pulmonary valve successful distal implantation of the valve was possible in 4/7 patients. Therefore these coronary anomalies should not be considered as primary contraindications for PPVI.

Repositioning an embolised stent during a percutaneous pulmonary valve implantation

Percutaneous pulmonary valve implantation is a less invasive procedure to treat right outflow tract dysfunction related to surgical procedures such as repair of Tetralogy of Fallot. Despite the lower risks, complications have been reported, namely embolisation of the pre-stent. We report a case of a 16-year-old boy, whose procedure was complicated by embolisation of the pre-stents and the strategy used to reimplant them, prior to the successful implantation of a pulmonary valve.