Left ventricular-right atrial communication in complete transposition of the great vessels

The pathologic features in three cases of complete transposition of the great vessels with a left ventricular-right atrial communication have been presented. This combination of malformations has not, to our knowledge, been reported before. Our three cases emerged from among 60 instances of complete transposition of the great vessels studied at necropsy. Clinical data were available in two of the three; both of these patients presented certain features which, when present in a cyanotic infant with congestive cardiac failure, should lead the clinician to suspect complete transposition of the great vessels with a left ventricular-right atrial communication. These features were in the auscultatory and electrocardiographic findings (which are similar to those observed in patients with a persistent common atrioventricular canal type of defect). They include a loud holosystolic and a diastolic murmur, accompanied by a thrill, and left axis deviation with a counterclock-wise QRS loop oriented around the mean manifest electrical axis, associated with right or combined ventricular hypertrophy. By conventional roentgenography and by venous angiocardiography, these patients could not be distinguished from those with the usual type of complete transposition of the great vessels. A selective left ventriculogram, however, would be expected to define the peculiar communication between the left ventricle and the right atrium, when present.