Is left ventricular superior to right ventricular pacing in children with congenital or postoperative complete heart block?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Is left ventricular superior to right ventricular pacing in children with congenital or postoperative complete heart block?' Altogether, 19 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Two large multicentric showed that site of pacing was the major determinant of left ventricular (LV) function with LV pacing being superior to RV pacing, though the number of patients paced via LV was lesser in comparison to right ventricular (RV). There were 2 prospective, 2 retrospective and 1 cross-sectional studies with fewer patients that demonstrated superiority of LV over RV pacing in preserving LV function. Only 1 small-scale retrospective study showed similar results of LV and RV pacing on LV function. One cross-sectional study showed superiority of LV apical pacing on exercise tolerance. As per the existing literature, LV apex seems to be the most optimal site for epicardial pacing while RV free wall pacing has the highest risk of causing LV dysfunction over the long term. We conclude that LV pacing appears to be superior to RV pacing in terms of long-term effect on cardiac function and ventricular synchrony.