Successful cardiac resynchronization therapy in a 3-year-old girl with isolated left ventricular non-compaction and narrow QRS complex: a case report.

Cardiac resynchronization therapy (CRT) is a new method of treatment for refractory heart failure. However, for children, its indication, efficacy, and long-term prognosis remain unclear. This study describes the use of CRT for a 3-year-old girl with intractable heart failure caused by isolated left ventricular non-compaction (LVNC) with narrow QRS complex. Echocardiography showed diffuse hypokinetic left ventricular (LV) wall motion (ejection fraction =29.3%) with dyssynchrony between the apex, posterior and lateral walls, where numerous prominent trabeculations existed, and severe mitral regurgitation. Biventricular resynchronization using epicardial pacing leads was performed under general anesthesia. Pacing sites for optimal synchronization in the ventricular walls where chosen using tissue Doppler imaging, and AV delay was adjusted to achieve maximal systolic blood pressure and maximal cardiac output. Over a follow-up period of 2 years, she exhibited significant and sustained improvement in LV function and clinical symptoms. BNP levels decreased from 1,960 to 82 pg/ml. QRS duration (103 ms) on ECG did not change after CRT. We conclude that pediatric CRT provides a highly useful adjunct for the treatment of heart failure, even in patients with a narrow QRS duration, and might improve the prognosis of patients with LVNC.