Improvement in lower limb vasodilatory reserve and exercise capacity in patients with chronic heart failure due to valvular heart disease.
OBJECTIVE
Reduced skeletal muscle blood flow during exercise is an important factor contributing to exercise intolerance in patients with chronic heart failure. Reactive hyperaemic blood flow is the maximum flow response necessary to protect tissue against ischaemia and hypoperfusion. We examined the vasodilatory response of the lower limb to ascertain whether response was increased with the improvement in exercise capacity observed after intracardiac surgery in patients with chronic heart failure due to valvular heart disease.


RESULTS
Calf blood flow in 23 patients was measured by venous occlusion plethysmography at rest and after a 5 min period of femoral occlusion. Immediately after this evaluation, peak oxygen uptake and anaerobic threshold were assessed by a symptom-limited cardiopulmonary exercise test using a bicycle ergometer. Both baseline calf blood flow and peak calf blood flow during reactive hyperaemia were significantly increased after surgery (baseline calf blood flow; from 2.6 +/- 0.2 to 3.8 +/- 0.4 ml.min-1 per 100 ml calf volume, P < 0.05: peak calf blood flow; from 17.5 +/- 1.3 to 25.4 +/- 2.6 ml.min-1 per 100 ml calf volume, P < 0.01). There was a significant correlation between changes in peak calf blood flow and improvement in exercise capacity (peak oxygen uptake; r = 0.42, P < 0.05; anaerobic threshold; r = 0.68, P < 0.0010).


CONCLUSIONS
These results indicate that exercise tolerance is improved with increased lower limb vasodilatory capacity after recovery from chronic heart failure.
Chiba
M
M
Second Department of Internal Medicine, Iwate Medical University, Morioka, Japan.
Nakamura
M
M
Kanaya
Y
Y
Kobayashi
N
N
Ueshima
K
K
Kawazoe
K
K
Hiramori
K
K
D000368:Aged; D002908:Chronic Disease; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000209:etiology / Q000503:physiopathology*; D006349:Heart Valve Diseases / Q000150:complications; D006439:Hemodynamics; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D014664:Vasodilation