Midwall ejection fraction for assessing systolic performance of the hypertrophic left ventricle

Sixty patients were enrolled in the study. Patients were divided into two groups with LVH (n = 30) and without LVH (control group, n = 30). LV systolic function was compared between the two groups and the relationships of left ventricular mass index (LVMI) with LV systolic parameters, including midwall EF, were investigated.Midwall EF in the LVH group was significantly lower than that in the control group (42.8±4.4% vs. 48.1±4.1%, p <0.0001). Midwall FS was also significantly lower in the LVH group (13.4±2.8% vs. 16.1±1.5%, p <0.0001), but EF did not differ significantly between the two groups. There were significant correlations between midwall EF and LVMI (r=0.731, p <0.0001) and between midwall FS and LVMI (r=0.693, p <0.0001), with midwall EF having the higher correlation.These results show that midwall EF can be determined using 2D STE. Midwall EF can be used to monitor LV systolic dysfunction, which is not possible with conventional EF. Evaluation of midwall EF may allow assessment of new parameters of LV systolic function in patients with LV geometric variability.Left ventricular (LV) systolic performance is often assessed by ejection fraction (EF) and fractional shortening (FS). It is said that despite depression of LV systolic function, LVEF and LVFS are preserved in patients with left ventricular hypertrophy (LVH) [1-6]. However, assessment of LV systolic function at the endocardial surface is thought to reflect a geometric change of the LV, rather than the contractile function of the myocardium [4]. Midwall FS has been used as a more physiologically appropriate measurement of LV systolic performance in patients with LVH, compared to conventional FS, and decreased midwall FS is predictive of subsequent morbidity and mortality [1-9]. However, calculation of midwall FS is based on a limited region of the LV, rather than the whole left ventricle. Therefore, evaluation of midwall FS for assessment of LV systolic performance may not be applicable in patients wi