Vasoreactivity before and after handgrip training in chronic heart failure patients

The purpose of this study was to investigate the vasodilatory and vasoconstrictor responses of the brachial artery in patients with chronic heart failure (CHF) and controls (CON) before and after a period of training and detraining. Methods: CHF (n = 10; age = 62 +/- 8 yrs) and CON (n = 10; age = 55 +/- 5 yrs) subjects completed 4 weeks of bilateral handgrip training (20 min; 60% of maximal handgrip strength; 15 grips*min(-1); 4 days*week(-1)). Handgrip strength was measured using a hand dynamometer. Brachial artery flow-mediated dilation (BAFMD) and cold pressor test (CPT) responses were determined using ultrasonography prior to training, at the end of 4 weeks of training and following 4 weeks of detraining. Absolute (mm) BAFMD and CPT responses were combined to yield a vascular operating range (VOR). Results: Baseline BAFMD was higher in CON (CHF: 2.98 +/- 1.49%; CON: 6.21 +/- 1.21%; p = 0.01), while CPT responses were higher in CHF (CHF: 3.38 +/- 0.83%; CON: 2.46 +/- 0.62%; p = 0.05). Baseline VOR tended to be greater in the CON subjects (CHF: 0.28 +/- 0.05 mm; CON: 0.32 +/- 0.12 mm; p = 0.06). Training increased handgrip strength (similar to 5%; p < 0.05, for both groups), BAFMD (CHF: 2.98 +/- 1.49% to 3.75 +/- 1.56%; CON: 6.21 +/- 1.21% - 8.02 +/- 1.75%; p = 0.01) and VOR (CHF: 0.28 +/- 0.05 mm - 0.3 +/- 0.09 mm; CON: 0.32 +/- 0.12 mm - 0.42 +/- 0.11 mm; p = 0.01). There were no significant changes in CPT responses. All markers approached pre-training values following detraining. Conclusion: Handgrip exercise increases strength, BAFMD and VOR in both CHF and CON subjects. These improvements are transient and return to pre-training values after removal of the training stimulus. (C) 2012 Elsevier Ireland Ltd. All rights reserved.