Right and left ventricular volume characteristics in children with pulmonary stenosis and intact ventricular septum.

Right (RV) and left ventricular (LV) volume variables were calculated in 27 patients with pulmonary stenosis (PS) during routine cardiac catheterization. These included 21 patients with isolated PS (group I) and seven studies in six patients (group II) with PS and right-to-left atrial shunt. Right and left ventricular volumes were calculated according to Simpson's rule and the area length methods respectively. In group I, right ventricular end-diastolic volume (RVEDV) was not different from normal, RVEF (0.70 +/- 0.02) was significantly higher than normal, and right ventricular stroke index (RVSI) (4.36/L/min/M2 +/- 0.23) was normal. The RVEDV/LVEDV ratio was significantly less than normal (P=0.001). Multiple regression analysis indicated that RVEDV (% of normal) decreased with both age and severity of RV outflow obstruction (r=0.77). In group II, RVEDV and RVSI were both less than normal (P less than 0.001), while RVEF was normal. LVEDV in the group was slightly higher than normal (P=0.026) while LVEF was less than normal (P=0.027) and resulted in normal LVSI. The data suggest that RV and LV function in children with isolated PS are normal, and that knowledge of the RV volume variables is not essential for the management of these patients. In contrast, hearts of patients with PS and right-to-left interatrial shunt have evidence that suggest depressed ventricular function, and the quantitation of RV volume may be helpful in the management of these patients.