Effects of long-term exercise training on cardiac baroreflex sensitivity in patients with coronary artery disease: a randomized controlled trial

Abstract

Objective: To investigate whether a structured long-term exercise training programme in patients with coronary artery disease affects baroreflex function and cardiorespiratory efficiency. Patients: Twenty-five elderly male patients with coronary artery disease. Methods: The patients were randomized into exercise (group A) or control group (group B). Group A followed a seven-month supervised exercise programme, consisting of three sessions of aerobic interval training weekly at moderate intensity. Twenty patients completed the study (group A: 10 patients and group B: 10 patients). At the beginning and end of the study, all subjects underwent a tilt test for the baroreflex sensitivity assessment and a graded exercise treadmill test with spiroergometry for the evaluation of their cardiorespiratory efficiency. Results: There were no differences between the two groups for any baseline variable. After training in group A, peak oxygen consumption, maximal treadmill tolerance time and anaerobic threshold were significantly increased by 21.9% (P < 0.001), 19.8% (P < 0.001) and 18.6% (P < 0.05), respectively. There were also significant increases in baroreflex sensitivity by 21.2% (P < 0.01), in baroreflex effectiveness index by 23.9% (P < 0.01), in event count by 45.1% (P < 0.01) and in ramp count by 13.2% (P < 0.05). Moreover, significant correlations were observed between the autonomic and cardiorespiratory parameters in group A at the end. Conclusion: The results suggest that long-term exercise training leads to beneficial effects on baroreflex activity and cardiorespiratory performance in coronary patients, and thus could constitute an efficient nonpharmacological intervention in this population.