Long-term follow-up after ventricular septal defect repair in children: Cardiac autonomic control, cardiac function and exercise capacity

OBJECTIVES: Survival after surgical repair of a ventricular septal defect (VSD) is good, but, as in almost all congenital heart diseases, late complications are frequent in adulthood. The exact mechanisms, timing and who is at risk are not fully understood. Altered cardiac autonomic nervous system (ANS) activity might play a role in these long-term sequelae. The aim of this study was to extensively evaluate children late after VSD repair including their cardiac ANS activity, cardiac function and exercise capacity.

METHODS: Thirty-three patients after surgical VSD repair and 66 healthy age-matched controls underwent 24-h monitoring of ANS control and cardiac output using impedance cardiography, detailed echocardiography and cardiopulmonary exercise testing.

RESULTS: Ambulatory cardiac ANS control was not different between the patients and the controls. Right ventricular function, exercise capacity and ambulatory cardiac output were decreased in patients compared with the controls. No relationships were found between cardiac ANS activity and cardiac function.

CONCLUSIONS: Long (average time after repair was 9.9 years) after successful surgical correction of a VSD, cardiac ANS control is not different from the controls. Right ventricular function and exercise capacity are impaired in VSD patients. Post-surgical outcome in these patients may be less benign than presently assumed; therefore, follow-up should be continued into adulthood to detect adverse outcomes in a timely fashion.