Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey

BackgroundChronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function.ObjectiveIn an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated.MethodsDemographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age 1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics.ResultsFrom 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n=147), RV endocardium (RVendo, n=113) or LV epicardium (LVepi, n=37). LVFS was significantly affected by pacing site (p=0.001), and not by maternal autoantibody status (p=0.266). LVFS in LVepi (39±5%) was significantly higher than in RVendo (33±7%, p