Pediatric Cardiology

Biography

Biography: Constance G. Weismann

Abstract

Background: Trans-catheter (TC) pulmonary valve replacement (PVR) has become common practice for patients with right ventricular outflow tract obstruction (RVOTO) and/or pulmonic insufficiency (PI). The aim of this study was to compare patients who received trans-catheter Melody valves to those who underwent surgical PVR before, and a t two time points following PVR. Methods: Retrospective review of echocardiograms obtained at three time points: last study before PVR, first study after PVR, most recent follow-up. We recorded patient characteristics and echocardiographic parameters of right ventricular (RV) and valve function. RVOTO was graded according to ASE guidelines for pulmonic stenosis (moderate: peak velocity 3-4m/s). Statistical methods included Chi-square, linear regression and mixed linear model to control for co-factors.
Results: We identified 76 patients who had undergone TC (N=42) or surgical (N=34) PVR between 2011 and 2014. Mean age was 21(±14) years. There was no difference between the groups in age or body surface area. At baseline, more patients in group TC had at least moderate RVOTO with or without PI (32/42 vs 3/34, p<0.001), and predominant PI was less common (10/42 vs. 29/34, p<0.001). At initial post-procedural echocardiogram there was no difference in valve function. 86% had at most mild RVOTO and 97% at most mild PI. At most recent follow-up, however, there was more valve dysfunction in the surgical group (moderate RVOTO 3/32 vs 10/26, p=0.03; mild or moderate PI: 0/32 vs 10/26, p=0.002). This remained significant after correcting for length of follow-up. 63 patients had quantitative assessment of RV function at a minimum of two time points. They were included in a mixed linear model that compared RV function between the groups, and controlled for predominance of RVOTO and/or PI prior to PVR. The TC group had an immediate increase in RV S’, but none of the other parameters changed significantly (table 1). Following surgical PVR there was an acute decrease of TAPSE, S’ and E’, that only partially recovered at follow-up.
Conclusion: Melody valve placement is associated with better pulmonary valve function in follow-up. Patients with surgical but not TC PVR had decreased RV function in follow-up, even when controlling for RVOTO and/or PI prior to PVR. Melody valve should therefore be the first choice for patients who are considered for PVR whenever possible.