Apoptosis of Cardiomyocytes in Children with Right Ventricular Pressure Overload with and without Hypoxemia

Background Cardiomyocyte apoptosis has been implicated in ventricular remodeling and initiation of cardiac failure. We sought to determine the severity of right ventricular (RV) cardiomyocyte apoptosis in cyanotic and acyanotic children with RV pressure overload. Methods Fourteen patients, seven with tetralogy of Fallot (group I) and seven with pulmonary stenosis and ventricular septal defect (group II), undergoing open‐heart surgery were studied. Right ventricular biopsies were examined for cardiomyocyte apoptosis by terminal deoxynucleotide transferase‐mediated dUTP nick‐end labeling. The magnitude of cardiomyocyte apoptosis was related to preoperative oxygen saturation and postoperative inotrope use and hospital stay. Results Compared with group I patients, group II patients were significantly older at operation (p = 0.002) and had a larger body size (p