Gender differences in left ventricular chamber and midwall systolic function in normotensive and hypertensive adults.

OBJECTIVE: Whether left ventricular (LV) systolic function differs between healthy men and women independent of afterload, LV geometry, age, heart rate and body size is disputed.
METHODS: We studied 517 clinically healthy adults without history of cardiovascular or endocrinal disease (age range 20-70, 274 with essential arterial hypertension). Echocardiography was used to assess LV geometry and systolic function both at endocardial and midwall levels.
RESULTS: Normotensive and hypertensive women had higher LV systolic function at endocardial and midwall levels independent of afterload. After adjustment for age, body surface area, heart rate and LV geometry, LV systolic function remained higher in women than in men in hypertensive and normotensive subjects. In a second set of multivariate analyses adjusting for age, body mass index, LV geometry and heart rate, women had significantly higher LV systolic function than men, both among normotensive and hypertensive subjects. In a reference group of 95 subjects with optimal blood pressure and normal body mass index (mean age 34 +/- 10; 32 men) extracted from the study sample, lower limits (5th percentile) of parameters of LV systolic function were higher in women than in men. Use of gender-specific partition values revealed that subnormal LV chamber function was uncommon in overweight, normotensive subjects as well as in hypertensive subjects; vice versa, stress-corrected midwall dysfunction was frequently subnormal in both normotensive, overweight (14%, mostly women) and in hypertensive subjects (18%, mostly men). At the opposite end of the spectrum, gender-specific supranormal, stress-corrected LV systolic chamber function (> 95th percentile of the distribution in the reference group) was relatively frequent in both overweight, normotensive (14%) and in hypertensive subjects (27%).
CONCLUSIONS: Clinically healthy hypertensive and normotensive women have higher LV chamber and midwall systolic function than men, independent of left ventricular geometry, body size, age and heart rate. Use of gender-specific partition values to define subnormal and supranormal LV systolic function revealed that, both in hypertensive and overweight normotensive subjects, subnormal LV chamber function was uncommon, whereas stress-corrected LV chamber systolic function was frequently supranormal. Vice versa, myocardial contractility was subnormal in approximately one-sixth of asymptomatic, normotensive overweight and of hypertensive subjects, with potentially unfavorable prognostic impact.