Browsing by Author "Gebauer, Roman A."

Background: Cardiac resynchronisation therapy (CRT) is increasingly used in children in a variety of anatomical and pathophysiological conditions, but published data are scarce. Objective: To record current practice and results of CRT in paediatric and congenital heart disease. Design: Retrospective multicentre European survey. Setting: Paediatric cardiology and cardiac surgery centres. Patients: One hundred and nine patients aged 0.24-73.8 (median 16.9) years with structural congenital heart disease (n=87), congenital atrioventricular block (n=12) and dilated cardiomyopathy (n=10) with systemic left (n=69), right (n=36) or single (n=4) ventricular dysfunction and ventricular dyssynchrony during sinus rhythm (n=25) or associated with pacing (n=84). Interventions: CRT for a median period of 7.5 months (concurrent cardiac surgery in 16/109). Main outcome measures: Functional improvement and echocardiographic change in systemic ventricular function. Results: The z score of the systemic ventricular end-diastolic dimension decreased by median 1.1 (p < 0.001). Ejection fraction (EF) or fractional area of change increased by a mean (SD) of 11.5 (14.3)% (p < 0.001) and New York Heart Association (NYHA) class improved by median 1.0 grade (p < 0.001). Non-response to CRT (18.5%) was multivariably predicted by the presence of primary dilated cardiomyopathy (p=0.002) and poor NYHA class (p=0.003). Presence of a systemic left ventricle was the strongest multivariable predictor of improvement in EF/fractional area of change (p < 0.001). Results were independent of the number of patients treated in each contributing centre. Conclusion: Heart failure associated with ventricular pacing is the largest indication for CRT in paediatric and congenital heart disease. CRT efficacy varies widely with the underlying anatomical and pathophysiological substrate.

Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. Objective In 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. Methods Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age < 18 years were retrospectively collected from patients undergoing chronic ventricular pacing (> 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. Results From 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< 0.001) and RVepi (35 +/- 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS<28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS >= 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was < 50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was < 50% in 17/18 (94%) LVepi-paced patients. Conclusion In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.