Abstract 14918: Mitral Valve Replacement With a Melody™ Valve Improves Survival for Young Children Compared to Mechanical Mitral Valve Replacement - A Case-Matched Control Study

Abstract

Introduction: Melody™ valve in the mitral position has been described for use in infants. Hypothesis: Melody™ valve (Medtronic) in the mitral position would improve survival compared to mechanical mitral valves for young children. Methods: Charts were retrospectively reviewed for children who had undergone a Melody™ valve insertion (MEL) between 2014 and 2020. MEL were case-matched by age and weight to those with a mechanical mitral valve (MECH). We compared transplant free survival and cumulative incidence of re-intervention. A sub-analysis was performed for children <1 year of age (8 MEL patients and their matches). Data are presented as median (interquartile range) or frequency (percentage). Results: Eleven children underwent Melody™ mitral valve replacement (MVR) over the study period. Age was 157 (104-402) days and weight 5.0 (4.2-7.4) kg. Indications for MVR were insufficiency in 6 (55%), stenosis in 3 (27%), and mixed disease in 2 (18%). MEL underwent a total of 13 repairs and 4 replacements (2 mechanical, 2 bioprosthetic) prior to Melody™ valve replacement. Final valve dilation size was 18 (15.5-18.5)mm. Two (18%) children salvaged from ECMO before MEL subsequently died. Three (33%) of the 9 survivors have required subsequent MVR at 9, 17, and 23 months; 1 for severe insufficiency, and 2 for severe mixed disease. The MECH cohort was not different in age, weight, valve size, bypass or cross-clamp times, indications for replacement, or number of prior repairs or replacements (p>0.10). At 1 and 3 years, transplant free survival (MEL: 80%, 80%; MECH: 82%, 64%; p=0.180) and re-intervention (MEL: 11%, 39%; MECH: 0%, 20% p=0.32) were equivalent between groups. For children <1 year of age, survival was higher in MEL (Figure; p=0.046) but rate of re-intervention remained equivalent (MEL: 17%, 34%; MECH: 0%, 29%; p=0.56). Conclusions: Melody™ MVR represents a better surgical strategy for infants less than 1 year of age requiring mitral valve replacement.