Impact of gender on the left ventricular cavity size and contractility in patients with hypertrophic cardiomyopathy

Backgound: The aim of the study was to assess gender-specific differences i n left ventricular cavity size, contractility and left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy. Methods: We studied retrospectively 129 referred patients with hypertrophic cardiomyop athy (77 males and 52 females). The echocardiographically measured left ven tricular end-systolic, end-diastolic dimensions, fractional shortening and occurrence of left ventricular outflow tract gradient greater than or equal to 30 mmHg were compared between sexes. Logistic regression analysis was u sed to calculate the predictive values of left ventricular dimensions and c ontractility for left ventricular outflow tract obstruction for each fender separately. Results: Left ventricular end-diastolic and end-systolic dimen sions were significantly smaller in females than males (41.7+/-5.3 vs. 45.1 +/-4.9 mm, P=0.0003; 23.1+/-44 vs. 25.6+/-5.3 mm, P=0.007 respectively). On the contrary, the value of fractional shortening was comparable in both se xes (44.7+/-7.3 vs. 43.6+/-7.9%, P>0.05). The left ventricular outflow trac t gradient occurred in females as frequently as in males (28.5 vs. 33.8%, P >0.05). By logistic regression analysis the predictors of left ventricular outflow tract gradient in females were left ventricular end-systolic diamet er (relative risk=0.74; confidence interval (CI) 0.61 to 0.91; P=0.0038), l eft ventricular end-diastolic diameter (relative risk=0.82; CI 0.72 to 0.96 ; P=0.0061) and fractional shortening (relative risk=1.11; CI 1.01 to 1.221 P=0.036). The most potent predictor appeared to be left ventricular end-sy stolic dimension. In males none of these parameters identified patients wit h left ventricular outflow tract obstruction. Conclusions: Females with hyp ertrophic cardiomyopathy featured smaller left ventricular cavity size, whi ch predisposed to left ventricular outflow tract obstruction (the most pote nt predictor of left ventricular outflow tract obstruction was left ventric ular end-systolic dimension). Higher left ventricular contractility also de termined left ventricular outflow tract gradient occurrence in females with hypertrophic cardiomyopathy. In males despite a larger left ventricular ca vity size the left ventricular outflow tract obstruction occurred with a si milar frequency as in females. Left ventricular outflow tract obstruction w as not predicted by left ventricular cavity size or contractility in males. (C) 2001 Elsevier Science ireland Ltd. All rights reserved.