RIGHT VENTRICULAR VOLUME CHARACTERISTICS BEFORE AND AFTER PALLIATIVE AND REPARATIVE OPERATION IN TETRALOGY OF FALLOT

Right heart volume data were obtained in 63 patients with Fallot''s tetralogy. The patients were divided into 3 groups: preoperative tetralogy (34); post shunt procedure (14); post repair without outflow patch (10); and post repair with an outflow patch (8). In Group 1 right ventricular [RV] end-diastolic volume (RVEDV), RV ejection fraction (EF) and RV systolic output (SO) were all mildly depressed. In post shunt patients, RVEDV was normal but RVEF remained depressed. RVEDV and RVSO increased following a shunt procedure, and these variables were larger in patients with a large vs. a small shunt. In Group 3A RVEDV, RVEF and RVSO were normal. In patients in Group 3B, RVEDV increased averaging 177 .+-. 15% of normal, RVEF was depressed averaging 0.45 .+-. 0.04, and RVSO was normal. RV size and pump function were abnormal in patients whose operation required an outflow tract patch; factors which may contribute to these abnormalities include a higher RV peak pressure, pulmonary incompetence and a larger noncontractile outflow tract. Longitudinal studies relating these variables to clinical performance and exercise testing will be important in assessment of the importance of these abnormalities.