3D Modeling of Self-Expandable Valves for PPVI in Distinct RVOT Morphologies

Abstract

Tetralogy of Fallot often requires transannular patch repair, leading to pulmonary insufficiency. Percutaneous pulmonary valve implantation (PPVI) with self-expandable valves offers a promising alternative, especially for enlarged right ventricular Queryoutflow tracts (RVOT). Five RVOT types identified in patients with Tetralogy of Fallot reflect anatomical variations due to disease and prior surgeries. This study assesses the Pulsta THV (R) valve's in vitro hemodynamic performance across these RVOT morphologies using 3D-printed models. Five RVOT morphologies were recreated as 3D models from patient-specific imaging data. The Pulsta THV (R) valves, available in 28, 30, and 32 mm sizes, were evaluated using the ViVitro Pulse Duplicator System at three cardiac outputs (2, 3.5, and 5 L/min). Hemodynamic performance was assessed by measuring regurgitation rates and pressure gradients in the left and right pulmonary arteries. The Pulsta THV (R) performed optimally in RVOT Types 1 and 2, demonstrating lower regurgitation rates and pressure gradients, particularly with larger valve sizes. Conversely, RVOT Types 3 and 5 showed increased pressure gradients and hemodynamic variability, indicating less favorable outcomes. The results highlighted the critical role of precise anatomical compatibility, with larger valve sizes proving more effective in enlarged RVOT geometry. Valve sizes tailored to specific RVOT morphologies can enhance PPVI outcomes. Types 1 and 2 are ideal for PPVI, while Types 3 and 5 present challenges due to hemodynamic variability. This study supports 3D modeling and in vitro testing for pre-procedural planning to reduce complications, with future research exploring dynamic imaging and materials mimicking tissue properties.