Effects of surgical septal myectomy on left ventricular wall thickness and diastolic filling.

This study was conducted to examine the late effects of surgical myectomy on left ventricular (LV) structure and diastolic function in patients with obstructive hypertrophic cardiomyopathy. Patients with hypertrophic cardiomyopathy who had complete echocardiographic studies before and > or =6 months after myectomy were included in this retrospective analysis of cavity dimension, septal and LV posterior wall thicknesses, and Doppler flow variables. Compared with preoperative measurement, mean septal thickness (23.6 vs 19.5 mm, p <0.001) and LV posterior wall thickness (14.2 vs 12.4 mm, p <0.001) were smaller after myectomy. Likewise, mitral inflow Doppler velocity curves indicated improvement in LV filling, with decreased mitral E velocity (0.95 to 0.87 m/s, p = 0.008). In conclusion, the long-term benefits of this operation may be mediated in part by favorable LV remodeling and changes in LV diastolic filling.