Mid-Term Longitudinal Assessment of Ventricular Function after Transcatheter Pulmonary Valve Replacement in Tetralogy of Fallot with or without Pulmonary Atresia.

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Patients who undergo surgical repair for TOF or TOF with pulmonary atresia (PA) may develop chronic severe pulmonary regurgitation (PR), which leads to right ventricle (RV) dilation and dysfunction. Pulmonary valve replacement is performed to restore pulmonary valve function and reverse the RV remodeling. Traditionally, pulmonary valve replacement has been performed surgically, but over the past two decades, transcatheter pulmonary valve replacement (TPVR) has emerged as an alternative approach. However, the optimal timing for TPVR remains a clinical challenge and a highly debated topic. Our study's primary aim is to evaluate the mid-term effect of TPVR on biventricular systolic function in patients with long-standing PR post-repair of TOF or TOF with PA. This retrospective single-center study included 30 patients with repaired TOF or TOF/PA who underwent first-time TPVR between 2012 and 2022. Echocardiographic assessments of right ventricular (RV) and left ventricular (LV) function were conducted at baseline and up to 3-5 years post-TPVR. Key parameters included RV fractional area change (FAC), RV strain, RV dP/dt, LV ejection fraction (EF), and LV longitudinal strain (LVLS). Statistical comparisons were made between pre- and post-TPVR time points. At baseline, most patients showed reduced RV and LV systolic function. Following TPVR, RV function did not show significant improvement on follow-up. However, LV longitudinal strain gradually improved over time and reached statistical significance at long-term follow-up (p = 0.004). LV EF showed an upward trend but did not reach significance. biventricular systolic function is decreased in many patients with repaired TOF or TOF/PA and long-standing severe PR. Transcatheter pulmonary valve replacement in this cohort resulted in improved LV strain but no improvement in RV function on mid-term follow up. These findings suggest the need to reconsider the timing of TPVR. Future studies should investigate whether earlier valve replacement could lead to better outcome of ventricular function in this patient population.