PE-454609-2 MARFAN SYNDROME AND VENTRICULAR ARRHYTHMIAS IN PEDIATRICS: MITRAL ANNULAR DISJUNCTION, MITRAL VALVE PROLAPSE OR BOTH – WHICH IS THE REAL CULPRIT?

Abstract

Mitral Annular Disjunction (MAD) and Mitral Valve Prolapse (MVP) have been associated with sudden death and ventricular arrhythmias (VA) in adults with connective tissue disease (CTD). While rare, there has been a case report of sudden cardiac death due to VA in a pediatric Marfan patient. However, risk factors have not been well described in this population. Our aim is to assess the association of MAD and MVP with VA in pediatric patients with Marfan syndrome. A retrospective single center cohort study was conducted and included all patients (≤ 21yrs) with clinical (based on Ghent’s criteria) and/or genetic diagnosis of Marfan syndrome. Clinical data including ambulatory cardiac monitoring and echocardiograms were reviewed prior to any mitral valve intervention, if applicable. 32 patients (38% female) with Marfan syndrome (66% with fibrillin 1 mutation) were included. The mean age was 13.5 ± 4.5 yrs. The results revealed MAD in 8 pts (25%), isolated MVP in 5 pts (16%) and bileaflet MVP in 14 pts (44%). Anterior MVP was seen in 16 pts (50%) and posterior MVP in 17 pts (53%). The mean MAD distance was 6.7 ± 2.3 mm. There was normal LV systolic function in 31 pts (97%). The median duration of cardiac monitoring was 58 hrs (IQR: 33-191). 26 pts (81%) had isolated ventricular ectopy (VE), 27 pts (84%) had complex VE (defined as couplets, triplets or NSVT), 4 pts (12.5%) had NSVT and none had sustained VT. The median VE per hour was 0.2 (IQR: 0-1). There was no R on T seen but short coupled VE (<350ms) was seen in 46% of isolated, 46% of couplets and 67% of triplets. Monomorphic ectopy was seen in 28% of isolated and 100% of couplets, triplets and NSVT. There were 5 total episodes of NSVT (Figure 1) with a mean HR of 159 ± 29 bpm, an absolute minimum HR of 94 bpm and maximum HR of 222 bpm. MAD was not associated with the presence of, or complexity in, ventricular arrhythmias. Anterior MVP was only associated with complexity in VE (p= 0.043), but posterior MVP and bileaflet MVP were not. MAD was associated with MVP (anterior, posterior and bileaflet; p= 0.026). There was a high incidence of complex VE and NSVT in this cohort of pediatric Marfan patients despite low overall ectopy burden. Anterior MVP but not MAD was associated with complexity in VE. However, MAD was associated with MVP. Larger studies are needed to better characterize MAD, including distance and circumferential extent, and MVP and their association with VA in pediatric patients with CTD.