[Non-invasive evaluation of right ventricular pressure in children with heart diseases: quantitative assessment by thallium myocardial imaging].

Abstract

201-thallium myocardial imaging studies were performed to evaluate systolic pressures in the right ventricle of 194 patients. These patients were classified to four groups. Group A (95 cases) consists of 77 patients with congenital cardiac disease, five patients with primary pulmonary hypertension, and 13 patients with history of MCLS. Congenital cardiac diseases included 30 patients with tetralogy of Fallot, 20 with ventricular septal defect, nine with atrial septal defect, and eight with pulmonary stenosis. Group B (35 cases); preoperative state of transposition of the great arteries. Group C (43 cases); post-operative state of congenital cardiac disease whose pre-operative right ventricular systolic pressures represented more than 70% of the left ventricular systolic pressures. This group included 31 patients with tetralogy of Fallot, seven with ventricular septal defect, four with atrial septal defect and one with patent ductus arteriosus. Group D (21 cases); post-operative state of transposition of the great arteries. Fifteen min after intravenous infusion of 30-50 microCi/kg 201-TlCl, myocardial images were obtained in five projections (anterior, LAO 30 degrees, 45 degrees, 60 degrees, and lateral). The angles were determined to demonstrate clearly the interventricular septum and the ventricular free wall. The images of end-diastolic phase were obtained using the ECG-synchronized gated method in each projection. The region of interest (ROI) was defined as a section or slice by drawing two lines perpendicular to the septum, and the counts of the systemic and pulmonic ventricular free wall (Cs and Cp) were analyzed to evaluate the pressure of the pulmonic ventricle. The pressures of the ventricles were obtained by cardiac catheterization performed concomitantly with the cardiac imaging.(ABSTRACT TRUNCATED AT 250 WORDS)