Nambiar L, et al. - Researchers tested the premise that poor exercise capacity in patients with a preserved left ventricular (LV) ejection fraction (LVEF) should be reflected in smaller LV dimensions, and a normal exercise capacity should be associated with larger LV dimensions, regardless of comorbidities. This was tested in a derivation cohort consisting of patients with normal chamber dimensions and preserved LVEF who underwent a clinically indicated treadmill stress echocardiogram using the Bruce protocol, as well as in a validation cohort, consisting of patients who had a Bruce-protocol treadmill exercise stress test and a separate transthoracic echocardiogram. A strong positive association was noted between LV volume and exercise capacity in patients with preserved LVEF and no evidence of myocardial ischemia referred for outpatient stress echocardiography.