[Function of the right ventricle in interauricular communication in adults]

This study was designed prospectively to analyze the influence of age and operation on right ventricular function in atrial septal defect; 17 patients were studied by means of radionuclide studies performed immediately before and approximately 6 months (5,8 +/- 2,3) after surgery. The pulmonary/systemic flow ratio (Qp/Qs) was determined by first pass technique, and right ventricular ejection fraction and peak filling rate were determined by equilibrium ventriculography. In addition, all patients had preoperative catheterization. According to age, patients were divided in group I (less than 35 years) and group II (greater than or equal to 35 years). Preoperatively, patients in group I, in comparison to group II, had better ejection fraction (48 +/- 8 vs 36 +/- 7; p less than 0.01), and better peak filling rate (3.7 +/- 0.9 vs 2.6 +/- 0.7; p less than 0.01), while Qp/Qs were not significantly different (2.5 +/- 0.8 vs 3.0 +/- 1.6) and pulmonary vascular resistances were less elevated (69 +/- 32 vs157 +/- 95 dynes/sec/cm-5; p less than 0.01). After surgery, right ventricular function did not significatively change in relation to preoperative data in both groups (ejection fraction: 44 +/- 13 and 34 +/- 5, respectively; peak filling rate: 3.3 +/- 1.4 and 2.1 +/- 0.6). We conclude that in atrial septal defect indexes of systolic and diastolic right ventricular function deteriorate with age, these changes being associated with a slight increase in pulmonary vascular resistance without changes of Qp/Qs; right ventricular dysfunction does not tend to improve postoperatively.