Surgical management of left ventricular outflow tract obstruction

Background: Left ventricular outflow tract obstruction (LVOTO) is caused by a spectrum of lesions. This study was performed to determine the outcomes of surgical management of LVOTO. Methods: All patients who had surgery of the LVOT between 2002 and 2010 were retrospectively reviewed. Results: There were 103 consecutive patients with median age 6.8 years (range 8 days to 62 years). Fourteen patients had simple subaortic membrane. Eighty-nine patients had complex LVOTO including fibromuscular obstruction (n = 53), tunnel obstruction (n = 22), hypertrophic cardiomyopathy/muscular obstruction (n = 15), and anomalies of the mitral subvalvar apparatus (n = 13). There were no early deaths. Mean LVOT gradient decreased from 33 mmHg (range 1 to 108 mmHg) to 6 mmHg (range 0 to 45 mmHg) (p < 0.001). Median follow-up was 3.8 years (range 0.9 to 8.5 years). There were three late deaths. Cumulative survival at one, three, and five years was 96% (95% CI 89% to 99%). All patients are in New York Heart Association classes I-II. Ten patients required reoperation (three for recurrent/residual LVOTO). Freedom from reoperation was 94%, 90%, and 78% at one, three, and five years (95% CI 86% to 98%, 80% to 95%, and 59% to 89%, respectively). No patient with complex LVOTO who had release of the fibrous trigones required reoperation [0% (0/26) vs. 16% (10/63) (p = 0.031)]. Factors associated with increased reoperation risk were interrupted aortic arch (OR 6.4, p = 0.22), atrioventricular septal defect (OR 15.4, p = 0.008), and higher mean LVOT gradient at discharge (OR 1.08, p = 0.023). Conclusions: Utilizing a multitude of operative strategies for surgery of the LVOT results in favorable early and midterm outcomes. Residual LVOTO and original cardiac diagnosis are associated with increased reoperation risk. Release of the fibrous trigones decreases reoperation risk in patients with complex LVOTO.