Exercise capacity varies by sex in aortic stenosis patients
Exercise capacity and its determinants differ between men and women with aortic stenosis, a recent study has found.
Through echocardiography and an exercise treadmill test (ETT), researchers assessed the exercise capacity of 316 patients with moderate or severe aortic stenosis. Ultrasound measurements included left ventricular (LV) wall thickness, chamber dimensions, stroke volume and ejection fraction.
Of the participants, 212 were men (mean age, 66±12 years) and 104 were women (mean age, 65±12 years). The latter had significantly higher resting heart rates at baseline, though both sexes reached comparable peak heart rate values. An early rapid rise in heart rate (RR-HR) occurred significantly more commonly in women (p=0.024).
In terms of exercise capacity, men were able to walk for a significantly longer time than women (10.4±4.3 vs 8.2±4.2 minutes; p<0.001) and achieved significantly higher metabolic equivalents (METs; 9.2±4.5 vs 7.6±4.3; p<0.001). A METs target of >10 was set and was satisfied by significantly more men than women (46 percent vs 29 percent; p=0.003).
In both sexes, RR-HR was a strong determinant of METs. Age and body mass index were predictive of METs only in men, while the global LV load was a strong determinant in women.
In multivariate analysis, the failure to reach 10 METs led to a more than sixfold increase in the risk of all-cause mortality in the overall sample (hazard ratio [HR], 6.21, 95 percent confidence interval [CI], 1.64–23.59; p=0.007). The same was true for men (HR, 5.53, 95 percent CI, 1.07–28.74; p=0.042), but the equivalent analysis was impossible for women due to a low number of events.