Clinical features of single ventricle with congenitally corrected transposition

Abstract

Nine patients with a single ventricle and the great vessel arrangement of congenitally corrected transposition are reviewed to emphasize the different clinical pictures which may be seen. Physical findings are not characteristic. Cyanosis is not always clinically detectable. Variable systolic murmurs are always present, but the most striking auscultatory finding, not stressed previously, is a decrescendo diastolic murmur of pulmonary insufficiency. Electrocardiographic features characteristic of congenitally corrected transposition of the great vessels include some type of arrhythmia, abnormal P waves, a Qr or QS pattern in lead aVR, and reversal of the normal precordial QRS pattern with a Q wave in leads V 3R or V 1 and no Q wave in V 6 or V 7. These findings, however, do not allow a distinction between cases with a single ventricle and those with other associated cardiac defects. Characteristic roentgenologic features of congenitally corrected transposition include a narrow cardiac base, a straight or slightly convex left upper cardiac border with absence of a definite pulmonary artery segment, an unusually cephalad position of the right pulmonary hilar shadows, a “waterfall” configuration of the dilated and tortuous right pulmonary artery, a huge main pulmonary artery causing an indentation on the left side of the barium filled esophagus, and a prominent shadow in the right superior mediastinum representing the displaced superior vena cava. These findings, although present in the majority of patients in this series, are not different from those found in cases of congenitally corrected transposition and two ventricles and a large ventricular septal defect. Cardiac catheterization and angiocardiography confirm the great vessel arrangement of corrected transposition and a bidirectional shunt in a ventricle whose systolic pressure is at systemic levels. Selective ventricular or subaortic angiocardiography is highly desirable to distinguish patients with a single ventricle in which a subaortic infundibular chamber is present from those with congenitally corrected transposition and two ventricles with a large ventricular septal defect. Although complete surgical correction of a single ventricle is not yet possible, pulmonary artery banding in patients with a large pulmonary blood flow may be a feasible palliative procedure.