Effects of short-term exercise training in patients with heart failure.

Heart failure is a debilitating disorder which limits exercise capacity and produces a poor quality of life. The present study was designed to determine the effects of an exercise training program on patients with CHF NYHA functional class II-III, attributed to left ventricular systolic dysfunction and dilated left ventricle. Twenty-two ambulatory male patients with stable CHF were randomised to a training (n = 15) and a control group (n = 7). A symptom limited ramp cardiopulmonary exercise test with gas exchange analysis was performed at baseline after 4 and 8 weeks. The training group underwent an exercise training program at 50% of peak oxygen uptake for eight weeks. The control group was not exercised. After 8 weeks, compared with baseline, there were statistically significant increase in peak oxygen uptake, peak workload, anaerobic threshold, oxygen pulse, RPP, ventilation and the duration of the test only in trained patients. The reduction in scores tested by the Minnesota Living with Heart Failure questionnaire (p < 0.001) and Borg dyspnea rating score (p < 0.001) reflect the reduction of symptoms and the improvement in health-related quality of life. Carefully selected patients with moderate to severe CHF can achieve significant improvements of exercise capacity and quality of life with exercise training and can safely participate in a conditioning program.

Comprehensive assessment of ventilatory functions of patients with chronic heart failure.

OBJECTIVE: A comprehensive assessment of the ventilatory functions of patients with chronic heart failure (CHF) both at rest and during a cardiopulmonary exercise test (CPET). We studied 42 males, divided into two groups--patients with CHF (n = 21) and age, weight, height and BMI matched healthy controls (n = 21). All subjects underwent a symptom-limited ramp CPET, arterial blood gas analysis, and complex functional examination of the pulmonary system. Subjective rating of dyspnea and exertion were measured by the Borg and ATS dyspnea scales. CHF patients showed a slight, but statistically significant decrease of the spirographic and diffusion parameters, as well as of the indices of respiratory muscle strength. There were no changes in blood gases and in tidal breathing parameters. The exercise capacity was markedly reduced (VO2peak ml.min-1 1352 +/- 335 CHF patients vs 2077 +/- 276 healthy controls; p < 0.001) and the anaerobic threshold occurred earlier (< 40% of predicted VO2peak) during CPET in CHF patients. The increase in VE/VCO2 in CHF patients (35.7 +/- 5.1 CHF; 28.9 +/- 2.5 HC, p < 0.001) indicates a compromised ventilatory efficiency which leads to a higher dyspneic cost of exercise (Borg peak 9.5 +/- 1.03 CHF; 6.0 +/- 1.28 HC; p < 0.001) as compared with healthy controls.