Spirometry in moderate chronic heart failure patients

Aim: To assess whether any change of ventilatory parameters after the maximum exercise and the aerobic training could be detected using simple spirometry. Material and methods: Sixteen patients (NYHA II, III; stable therapy; mean age 51 +/- 5.2 years, left ventricular ejection fraction 31 +/- 5%, peak oxygen consumption 18.9 +/- 5.9 ml . min(-1) . kg(-1)) underwent bicycle spiroergometry which represented the maximum exercise stress. They were randomized into two groups thereafter. Eight of them passed a three month intensive aerobic training at the ventilatory threshold level. The control group comprised the other eight patients. Spirometric parameters were measured using Vicatest PC (Mijnhardt). The parameters before and after the initial spiroergometry as well as at the beginning and at the end of the three month period have been tested. Results: The maximum expiratory medium flow (MEMF) was the only spirometric variable affected by the spiroergometry (4.3 +/- 1.4 vs. 4.0 +/- 1.11 . s(-1); p<0.05). The maximum voluntary ventilation (MVV) (126 +/- 26 vs. 144 +/- 32 1 . min(-1); p < 0.05) and the peak expiratory now (PEF) (8.8 +/- 2.5 vs. 9.7 +/- 2.51 . s(-1); p < 0.05) increased in the training group without any change of other parameters. The MVV (134 +/- 26 vs. 118 +/- 26 1 . min(-1); p < 0.05) and the expiratory vital capacity (EVC) (4.4 +/- 0.8 vs. 4.1 +/- 0.71; p < 0.05) decreased significantly in the control group. Conclusions: In stable moderate chronic heart failure patients the short-term symptom-limited exercise stress does not affect significantly the main spirometric functions. On the other hand the intensive exercise therapy may provide a positive effect.