Excision of anomalous muscle bundles as an important addition to extended septal myectomy for treatment of left ventricular outflow tract obstruction.

OBJECTIVE

This study aims to report our preliminary experience and anatomic findings in the surgical treatment and postoperative management of hypertrophic obstructive cardiomyopathy.

METHODS

This study included 277 patients with hypertrophic obstructive cardiomyopathy (168 [60.65%] were male), with a median age of 47 years (interquartile range, 35-54 years), who underwent surgical myectomy performed by 1 surgeon in Fuwai Hospital between May 2010 and April 2015. The median follow-up was 14 months (interquartile range, 7-24 months).

RESULTS

A total of 127 patients (45.85%) underwent concomitant procedures, and 2 patients (0.72%) died in the early perioperative days. The left ventricular outflow gradient decreased from 78 mm Hg (interquartile range, 61-100 mm Hg) to 11 mm Hg (interquartile range, 8-15 mm Hg) when discharged (P < .001). Of the 228 patients with well-documented anatomic description, more than 80% had various intraventricular anomalies. The cumulative survival was 99.28% (95% confidence interval, 97.15-99.82) at 1 year and 96.98% (95% confidence interval, 92.56-98.79) at 5 years. Of the surviving 272 patients, 268 (98.53%) were categorized with functional class I and II of the New York Heart Association classification at the latest evaluation.

CONCLUSIONS

Anomalous muscle bundles are common in hypertrophic obstructive cardiomyopathy, and they may lead to middle-apical obstruction. Surgical myectomy provides excellent clinical outcomes with low risk for sufficient relief of obstruction and radical correction of intraventricular anomalies in patients with hypertrophic obstructive cardiomyopathy.