Success and limitations of right ventricular sinus myectomy for pulmonary atresia with intact ventricular septum

Objectives Right ventricular sinus myectomy has been proposed for pulmonary atresia with intact ventricular septum for morphology falling within the uncertain area for eventual biventricular repair. Our objective was to evaluate right ventricular sinus myectomy by characterizing the morphologic spectrum of these patients, determining whether biventricular repair was achieved, ascertaining growth of right-sided structures, and assessing survival. Methods We evaluated medical records, all imaging studies, and follow-up data (complete in all but 1 patient) from 43 patients with pulmonary atresia with intact ventricular septum treated from October 1993 to July 2005, 16 of whom underwent right ventricular sinus myectomy. Serial echocardiographic measurements of right-sided cardiac structures were converted to Z values to estimate their growth relative to somatic growth. Results Patients undergoing right ventricular sinus myectomy had mild-to-moderate right ventricular size diminution (grade −1.2 ± 3.2) and a tricuspid valve Z value of −4.9 ± 1.9. Thirteen (87%) of the 16 patients achieved biventricular repair. After right ventricular sinus myectomy, mean right ventricular cavity size grade increased to 1.4 ± 0.66, but the tricuspid valve Z value did not change appreciably over time. Five-year survival after sinus myectomy was 85%; late deaths were in patients with the smallest tricuspid valves at presentation ( Z value