DETERMINANTS OF EXERCISE CAPACITY AND EXERTION PERCEPTION IN PATIENTS WITH PERSERVED LV FUNCTION
Jason Lazar, MD
Luther Clark, MD
Louis Salcoccioli, MD
SUNY Downstate Medical Center
Division of Cardiology
Symptoms of congestive heart failure (CHF) are often present in patients with preserved left ventricular systolic function. In this setting, indices of diastolic filing have been found to be predictive of exercise capacity. There exists considerable variability in exercise capacity in patients without heart failure referred for exercise stress testing. While structural heart disease is found in a relatively small proportion, other factors are likely responsible for the reduced exercise tolerance in these patients. Reduced exercise tolerance may manifest as decreased exercise duration or as enhanced perception of exertion. A number of studies have found that indices of left ventricular (LV) diastolic filling correlate with exercise time in select patient populations including hypertensives and the elderly. However, no study has specifically addressed exercise tolerance in terms of both exercise duration and perceived effort. Therefore, the objective was to determine echocardiographic correlates of exercise capacity and of perceived exertion in patients without structural heart disease.
This study found that in a group of healthy subjects with normal LV systolic function referred for exercise stress echocardiography, exercise duration was inversely and independently related to age. RPE was directly and independently related to LA size. Both exercise duration and RPE were unrelated to resting indices of LV systolic and diastolic function. The mechanism(s) by which LA size modulate perception of exertion merit further study.
Research: Pediatric Psychology,
Analytical & Materilas Chemistry, Biomedical: Cardiovascular Medicine
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