Ventricular volume characteristics of single ventricle before corrective surgery.

With use of biplane cineangiocardiograms, ventricular cavity volume measurements were determined in 17 patients with single ventricle, before total correction. There were 4 patients with a single left and 13 with a single right ventricle. Atrioventricular (A-V) valve regurgitation was evident in 6 of 13 patients with a common A-V valve. End-diastolic volume index ranged from 72 to 282 ml/m2 (average 131 ml/m2), and these values ranged from 71 to 206 percent (average 110 percent) of the sum of the normal left and right ventricular end-diastolic volumes. Ejection fraction averaged 0.55. There was no significant difference in ventricular cavity volume characteristics and ventricular function between patients with single and and single right ventricle. The single ventricle ejects blood to both the systemic and the pulmonary circulatory beds. There was a high correlation of end-diastolic volume index with pulmonary to system flow ratio (r = +0.89, p less than 0.001). This observation indicates that the major factor affecting ventricular cavity volume in single ventricle is pulmonary blood flow and a systemic to pulmonary arterial shunt should increase the ventricular cavity volume. Ventricular function of single ventricle was depressed. The ejection fraction of patients with A-V valve regurgitation averaged 0.49, which was significantly lower than that (0.58) of patients without regurgitation (p less than 0.05). A-V valve regurgitation was also a factor that increased ventricular cavity volume, although the ventricular function became more depressed.