Left ventricular diastolic filling and cardiovascular functional capacity in older men

We investigated anaerobic threshold (thetaL) gas exchange kinetics and maximal oxygen uptake (V̇O2,max) among older men with reduced left ventricular end-diastolic filling (LVDF). Ten men (mean age, 73 years) with LVDF impairment and low fitness, but without other cardiovascular dysfunction were studied. Treatments compared to control included: 5 days, high intensity exercise training protocol; 5 days, calcium channel blockade (240 mg verapamil); 21 days, detraining/washout; and 5 days, combined treatments. Results indicated no changes in resting left ventricular systolic function with any treatment. Significant resting diastolic function changes included increased early:late flow velocity (control, 0.87; training, 1.28; verapamil, 1.32), and a decreased isovolumic relaxation time (control, 0.10 s; training, 0.08 s; verapamil, 0.08 s). The combined treatments were not additive. Sub-threshold oxygen uptake kinetics (tauVO2, s) were significantly faster following either training or verapamil (tauVO2,control, 62 ± 12; tauVO2,training, 44 ± 9; tauVO2,verapamil, 48 ± 10) and combined treatments (tauVO2, 41 ± 8). V̇O2,max (ml kg-1 min-1) was significantly increased (control, 21.8 ± 2.2; training, 27.3 ± 2.2; verapamil, 25.2 ± 3.4; combined treatments, 26.9 ± 2.3). Increasing ventricular preload with either exercise training or calcium channel blockade was coincident with faster tauVO2 and increased V̇O2,max.