Impact of Conventional Versus Biventricular Pacing on Hemodynamics and Tissue Doppler Imaging Indexes of Resynchronization Postoperatively in Children With Congenital Heart Disease

Impact of Conventional Versus Biventricular Pacing on Hemodynamics and Tissue Doppler Imaging Indexes of Resynchronization Postoperatively in Children With Congenital Heart Disease Phat P. Pham, Seshadri Balaji, Irving Shen, Ross Ungerleider, Xiaokui Li, David J. Sahn We studied the effects of atrial, conventional dual-chamber, and biventricular pacing in 19 children with congenital heart disease in the early postoperative period. Cardiac index and tissue Doppler echo data were measured. Cardiac index was improved by biventricular pacing. The tissue Doppler imaging-derived strain rate indexes of dyssynchrony showed worsening with conventional dual-chamber pacing but improvement with biventricular pacing. These findings suggest that short-term biventricular pacing may benefit children with congenital heart disease repair in the postoperative period. We sought to evaluate the effects of biventricular (BDOO) pacing compared with conventional (CDOO) atrioventricular (AV) sequential and atrial (AOO) pacing in children and infants in the early postoperative period after open heart surgery for congenital heart disease (CHD). Biventricular pacing using right ventricular (RV) and left ventricular (LV) leads can improve hemodynamics in patients with CHD, but it is unclear whether this occurs in early postoperative children with CHD. Nineteen children (age, 5 days to 5.4 years; median, 5.5 months) with a definitive biventricular repair for CHD underwent AOO, CDOO, and BDOO pacing with temporary epicardial leads for 10 min each. The AV delay was 80% of the PR interval for the CDOO and BDOO modes. Lead placement was two right atrial, two RV, and one LV. Blood samples for cardiac index (arterial and venous) and tissue Doppler (TDI) traces were obtained in each pacing mode with a Vivid 7 BT04 digital ultrasound system (GE/VingMed, Horten, Norway) from an apical four-chamber view and analyzed with EchoPac software. The QRS duration was significantly shorter for BDOO compared with CDOO, and the cardiac index was higher with BDOO compared with CDOO. Systemic blood pressure was not different between the three modes of pacing (AOO, CDOO, BDOO). The TDI-derived strain rate showed minimal dyssynchrony in AOO as seen by isovolumic tensing (IVT) and peak systolic contraction (PSC) timing differences between RV and LV. The CDOO worsened dyssynchrony with prolonged ΔIVT and PSC. The BDOO showed improved synchrony as seen by ΔIVT and PSC. The TDI-derived strain rate showed worsened