Vasoreactivity before and after handgrip training in chronic heart failure patients.

UNLABELLED: 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 (∼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.