Homograft valve insertion for pulmonary regurgitation late after valveless repair of right ventricular outflow tract obstruction.

OBJECTIVE: Pulmonary regurgitation after valveless repair of right ventricular outflow tract obstruction (RVOTO) results in progressive right ventricular (RV) dilatation and dysfunction in an increasing number of patients. Since 1989, we have exclusively used cryopreserved homografts to restore pulmonary valve competence in these patients. Our 9-year-experience with pulmonary valve insertion (PVI) in such cases has been reviewed to evaluate the indications for this procedure and its benefits.

METHODS: From 1989 to 1998, 49 patients (original diagnosis: tetralogy of Fallot in 42 patients and pulmonary stenosis in seven) aged from 3 to 42 years (mean 18 +/- 9 years) underwent PVI with homografts late (mean 13 +/- 7 years) after valveless repair of RVOTO (transannular patch, n = 38; pulmonary valvulotomy therefore tau chi infundibular patch, n = 11). Preoperatively, all patients had severe pulmonary regurgitation, cardiomegaly, significant to severe RV dilatation and dysfunction, fatigue, reduced exercise tolerance, and were in NYHA class II (n = 43) or III (n = 6). Ten patients had ventricular arrhythmia.

RESULTS: There was one early death, due to air embolism, and one late death, due to ventricular arrhythmia. All survivors but one, who subsequently underwent heart transplant, had symptomatic improvement after homograft insertion. The mean RV end-diastolic diameter decreased from 38 +/- 9 to 26 +/- 8 mm (P < 0.01), and cardiothoracic ratio decreased from 0.62 +/- 0.07 to 0.54 +/- 0.04 (P < 0.01). Good late homograft function was the rule, with all the survivors being free of reoperation for valve failure. At a mean follow-up of 42 +/- 28 months, 41 patients (87% of the survivors) were in New York Heart Association (NYHA) class I and six in class II. Within this group three patients are still in treatment for RV failure and five for ventricular arrhythmias. In these patients, the average interval between RVOTO repair and PVI was significantly longer than in the others (18 +/- 7 vs. 12 +/- 6 years, P < 0.01).

CONCLUSION: Homograft PVI is safe and provides clinical improvement with a significant reduction in RV volume overload and excellent mid-term results in most patients with severe PR late after RVOTO repair. This procedure should be undertaken early in symptomatic patients, before severe RV failure and ventricular arrhythmias ensue.