Effects of exercise training on forearm and calf vasodilation and proinflammatory markers in recent heart transplant recipients: a pilot study

Background Aerobic exercise training improves vasodilatory capacity of peripheral resistance vasculature and modifies plasma proinflammatory markers in chronic heart failure patients. It is, however, currently unknown whether aerobic exercise has a similar effect in heart transplant recipients (HTR). Design and Methods Eight weeks after transplantation, 14 HTR were randomly assigned to 12 weeks of supervised aerobic exercise training (TRAINED; n = 8) or attention-time control (CONTROL; n = 6) in addition to posttransplantation medical care. Peak forearm blood flow and calf blood flow (CBF) during reactive hyperemia after 5 min of limb ischemia was used as a measure of endothelium-dependent vasodilation of limb resistance arteries. Plasma C-reactive protein, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), soluble intercellular adhesion molecule-1 (sICAM-1), and exercise capacity were measured at baseline and again after 12 weeks in both groups. Results Peak CBF increased 22% in the TRAINED (25.9 +/- 5.8-31.6 +/- 7.9 ml/min/100ml, P<0.05), but there was no change in peak CBF after 12 weeks in CONTROL. Plasma C-reactive protein, IL-6, TNF-alpha, sICAM-1 did not change in TRAINED, but there was a significant increase in TNF-alpha (1.66 +/- 1.02 vs. 3.07 +/- 1.10 pg/ml, P<0.05), and sICAM-1 (205.9 +/- 59.1 vs. 245.0 +/- 47.9 ng/ml, P<0.01) in CONTROL after 12 weeks. Furthermore, exercise test duration improved 51.7% (P<0.01) and there was a trend toward an increase in peak VO2 (P=0.05) in TRAINED after 12 weeks but neither changed in CONTROL. Conclusion A program of supervised aerobic exercise improves endothelium-dependent vasodilation of the calf, but not forearm resistance arteries, and may attenuate a progressive increase in selected proinflammatory markers in HTR.