Successful cardiac resynchronization therapy in a 9-year-old boy with dilated cardiomyopathy.

Despite increasing clinical impact of cardiac resynchronization therapy (CRT) with av-synchronous biventricular pacing in adults with dilated cardiomyopathy (DCMP), an ejection fraction (EF) of less than 35% and left bundle branch block (LBBB), there is still only little experience in children. We report on a 9-year-old boy with histologically proven DCMP and LBBB who had fulfilled the criteria for heart transplantation (HTX) after cardiac decompensation including catecholamine therapy. A transvenous CRT pacing system was implanted without technical difficulties. The healing process was uneventful. With optimized AV-interval invasive evaluation during implantation indicated a 16% pulse pressure increase and a 63% augmentation of LV dp/dt by pacing the LV 20 ms prior to the RV. Tissue Doppler imaging demonstrated complete LV resynchronization. Physical capacity increased and HTX could be delayed.