Abstract 4140065: Feasibility of Self-Expanding Transcatheter Pulmonary Valves in Patients with Pyramidal RVOT: Favorable Mid-term Outcomes

Background: Transcatheter pulmonary valve replacement (TPVR) has been acknowledged as a common and beneficial treatment for significant pulmonary regurgitation (PR), but data are still lacking about the mid-term effects of self-expanding valve implantation in patients with pyramidal right ventricular outflow tract (RVOT). Methods: This study was a multicenter retrospective analysis involving consecutive patients who underwent intentional TPVR between May 27, 2014, and September 14, 2023. Baseline characteristics and immediate/mid-term echocardiographic variables were gathered and compared among patients with pyramidal RVOT and those with other RVOT configurations. The primary endpoint of immediate device success rate and secondary endpoint within one year post-procedure were also evaluated in both groups. Results: A total of 68 patients were enrolled in the study. The primary endpoint showed a marginal difference between the two groups, with a significance level of P = 0.067 (86.7% in the pyramid-type group versus 100% in other types). At 1-year follow-up, the secondary endpoint demonstrated no intergroup differences in outcome (91.7% versus 86.0%; P = 0.605). Echocardiographic improvement and mid-term clinical outcomes were comparable in both groups (all P > 0.05). However, prosthesis valves implanted in pyramidal RVOT were observed to be more prone to developing trivial regurgitation within the first month (6 out of 11, 54.5% versus 7 out of 45, 15.6%; P = 0.016). Conclusions: Despite slightly lower immediate device success rates, the outcomes of Venus P-Valve implantation in pyramidal RVOT were not only acceptable but favorable during mid-term echocardiographic and clinical follow-up. The utilization of self-expanding valves has significantly broadened the indications for TPVR, necessitating specific morphology assessments to better guide future procedures.