Bench Testing of Multiple Valve-in-Valves Within a Large Housing Self-Expanding Pulmonary Valve

Lifetime management of patients with large dysfunctional right ventricular outflow tract (RVOT) should incorporate a predefined strategy for valve-in-valve (ViV) treatment. The choice of the initial self-expanding platform may determine the feasibility, equipment and interventional techniques required for subsequent ViV procedures. This study was performed to demonstrate bench-test feasibility of multiple ViV within a large self-expanding pulmonary platform, the VenusP-valve (Venus Medtech). Bench testing was performed using a modular, human-grade anatomical right heart simulator (SimuPULS Pulmonary platform, Simulands). Continuous real-time monitoring was performed using biplane angiographic system and four synchronized cameras. Sequential ViV implantation was performed using progressively smaller VenusP-valves (34 mm, 32 mm, 30 mm) deployed within the initial 36 mm VenusP-valve. Subsequently, a 29 mm balloon-expandable valve (Vitae, Venus Medtech) was implanted within the multi-layered self-expanding valves. Fluoroscopic measurements of the self-expanding valve frame demonstrated minimal under expansion (~ 2 mm) of the tubular section. Final measurements confirmed appropriate expansion of the balloon-expandable valve within the complex of four previously implanted self-expanding valves. The external diameters of the tubular section at peak balloon inflation and after balloon deflation demonstrated minimal recoil (< 1 mm). Final external diameters did not exceed the nominal diameter of the initial 36 mm valve. Valve-in-valve implantation within a large-frame self-expanding valve, enables sequential implantation of progressively smaller self-expanding valves whilst still preserving the option for subsequent implantation of a large balloon-expandable valve. These bench findings may support clinical decision making and ViV planning for percutaneous lifetime management of patients with dysfunctional RVOT.