Chronic congestive heart failure after repair of tetralogy of Fallot.

The etiology of chronic congestive heart failure (CHF) after repair of tetralogy of Fallot was determined in 102 patients consecutively catheterized 1 to 12 years postoperatively. Chronic CHF was observed in 36/102 patients. The most prevalent abnormality leading to congestive failure (31/36) was a large residual ventricular septal defect alone or in combination with other lesions. All postoperative patients with pulmonary to systemic flow ratios greater than 2:1 (25/102) had congestive failure and evidence of biventricular dysfunction. Significant tricuspid regurgitation (N = 11) and persistent systemic to pulmonary artery shunts (N = 6) contributed to volume overload and congestive failure in the patients with large residual ventricular septal defect. Isolated severe residual right ventricular outflow tract obstruction was a common cause of chronic CHF. Pulmonary artery hypertension was present in 20/36 patients with CHF. The increased pulmonary pressure was not wholly due to an increased pulmonary flow since 7/20 patients had pulmonary vascular resistance greater than 3 mm Hg/L/min/m2. Our findings indicate that persistent or chronic congestive heart failure in postoperative tetralogy of Fallot patients requires bilateral cardiac catherterization since an identifiable and surgically correctable lesion is nearly always present.