Contribution of left ventricular diastolic function to exercise capacity in normal subjects

Abstract

Previous studies have established that most of the heterogeneity in exercise capacity seen with sedentariness, aging, or physical training can be accounted for by individual differences in the maximal rate of total body oxygen consumption (VO2 max) during dynamic exercise. However, the factors that limit VO2 max in normal subjects remain disputed. To test the hypothesis that differences in left ventricular diastolic performance contribute to the heterogeneity of VO2 max seen in healthy subjects, 57 normal sedentary volunteers (36 +/- 13 yr, range 20-76 yr) and 9 endurance athletes (37 +/- 8 yr, range 26-51 yr) were studied. Aerobic capacity was estimated as VO2 max during a multistage dynamic cycle exercise protocol, whereas resting left ventricular systolic and diastolic function was assessed by two-dimensional and Doppler echocardiography. The relationship of the left ventricular functional indexes with VO2 max was investigated by stepwise multiple regression analysis. VO2 max ranged from 25 to 58 ml.kg-1 x min-1 in sedentary subjects and from 44 to 60 ml.kg-1 x min-1 in athletes. With univariate analysis, significant correlations were observed between VO2 max and age (r = -0.60), maximal heart rate (r = 0.48), maximal work load (r = 0.80), left ventricular volumes at both end diastole (r = 0.51) and end systole (r = 0.62), peak early transmitral filling velocities (r = 0.80), and the ratio of early to late transmitral filling velocities (r = 0.87).(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise Training Improves but Does Not Normalize Left Ventricular Systolic and Diastolic Function in Adolescents With Type 1 Diabetes

“…Blood volume increases with chronic exercise training (19), and endurance-trained athletes rely on increased total blood volume and increased rates of diastolic filling to achieve greater stroke volume during exercise (20,21 The improved ejection fraction seen with training in our adolescent population agrees with previous studies in healthy individuals (24). However, unlike adults, in whom changes in end-diastolic volume underlie improved ejection fraction (25), the adolescents with type 1 diabetes in this study appeared to rely more on reductions in end-systolic volume to increase stroke volume and ejection fraction after training (24). Indeed, the reductions in resting end-systolic volume and ejection fraction, without changes in total peripheral resistance or arterial blood pressure, are consistent with increased resting contractility.…”

Left Ventricular Diastolic Filling and Cardiovascular Functional Capacity in Older Men

“…Poor diastolic function may be evident in many older subjects and include sedentary ageing (Cacciapuoti et al 1992), hypertension (Petrella et al 1994), and low aerobic fitness (Vanoverschelde et al 1993). For example, Cuocolo et al (1990) showed that hypertensive patients with reduced ability to increase end-R. J.…”

Contribution of Exercise-Induced Mitral Regurgitation to Exercise Stroke Volume and Exercise Capacity in Patients With Left Ventricular Systolic Dysfunction

“…Their interobserver and intraobserver variability has been reported previously. 5,14 Comparisons between groups were performed by use of the Student t test for paired or unpaired data, the Fisher exact test, or 2 contingency analysis (with Yates' correction), where appropriate. All tests were 2-sided, and a probability value Ͻ0.05 was considered statistically significant.…”

“…[1][2][3][4][5][6] Although the mechanisms of exercise intolerance are multifactorial, they depend at least in part on the maximal pumping capacity of the heart, ie, maximal stroke volume and cardiac output.…”