Are there sex differences in regional systolic function and wall stress in hypertrophic obstructive cardiomyopathy? A three-dimensional echocardiography study

Abstract

Objectives Sex-related differences in left ventricular (LV) systolic function have been previously reported in patients with aortic stenosis and hypertensive heart disease. The goal of this study was to determine systolic function of the LV in male and female patients with hypertrophic obstructive cardiomyopathy and to relate it to wall thickness and wall stress, respectively. Background Wall thickening, a parameter of regional systolic function, is determined by wall thickness and wall stress. A comprehensive analysis of regional LV function was performed from multiplane transesophageal echocardiography with 3-dimensional reconstruction of the LV. Methods In 21 patients (11 men and 10 women) 4 parallel (2 basal and 2 apical) equidistant short-axis cross sections from base to apex were obtained from the reconstructed LV. In each short axis, 24 wall-thickness measurements were carried out in 15-degree intervals at end-diastole (ED) and end-systole. Thus, a total of 192 measurements were obtained in each patient. Wall thickening, a parameter of regional systolic function, was calculated as the difference of ED and end-systolic wall thickness, and fractional thickening as thickening divided by ED thickness. Results Fractional thickening and wall stress were inversely related to ED wall thickness in both men and women. Women showed better LV systolic function when compared with men ( P < .001). However, when corrected for wall stress, which was lower in women, there was no sex difference in systolic function. Conclusions There are regional differences in LV systolic function in men and women that depend on regional wall thickness and wall stress.