Surgery insight: Septal myectomy for obstructive hypertrophic cardiomyopathy--the Mayo Clinic experience.

Septal myectomy has been the gold standard treatment for the relief left ventricular outflow tract obstruction and cardiac symptoms in both adults and children with obstructive hypertrophic cardiomyopathy. In almost all circumstances, abnormalities of the mitral valve and subvalvar mitral apparatus can be managed without the need for mitral valve replacement, and other cardiac lesions can be repaired simultaneously. In the current era, the operative mortality for isolated septal myectomy at an experienced center is low in both children and adults (approximately 1%). Excellent late results with myectomy are gratifying: 90% of patients improve by at least one NYHA class, and improvements persist in most individuals on late follow-up. Late survival in patients with obstructive hypertrophic cardiomyopathy who undergo myectomy exceeds that of patients who do not receive surgical treatment and, in addition, myectomy may be associated with reduced long-term risk of sudden cardiac death. These results should serve as a basis for comparison with newer nonsurgical treatment regimens.