Article

Patients with chronic heart failure (CHF) present with microcirculation
alterations, partially attributed to endothelial dysfunction. Exercise training
has been shown to induce beneficial effects in CHF patients. The aim of our study
was to assess the effect of physical exercise on the microcirculation of CHF
patients by near-infrared spectroscopy (NIRS). METHODS: Sixteen consecutive
stable CHF patients (men, n = 10; mean age = 50 +/- 12 years) participated in a
3-month rehabilitation program (3 sessions per week). All patients performed
symptom-limited, ramp-incremental cardiopulmonary exercise testing on a cycle
ergometer before and after the completion of the program. Measurements included
peak oxygen uptake (VO2peak), VO2 at anaerobic threshold (AT), and first-degree
slope of VO2 during the first minute of recovery (VO2/t slope). Tissue oxygen
saturation was continuously measured by NIRS at the thenar muscle during a
3-minute vascular occlusion with a pneumatic cuff (occlusion technique) before
and after the rehabilitation program. RESULTS: The oxygen reperfusion rate
(%/min) following the release of vascular occlusion increased significantly after
the rehabilitation program (450 +/- 105 to 532 +/- 151, P = .004) as did vascular
reactivity (from 27 +/- 13%/min to 39 +/- 21%/min, P = .006). In addition, there
was a significant increase in VO2peak and AT (from 14.3 +/- 4.7 mL . kg . min to
16.7 +/- 6.3 mL . kg . min and from 9.5 +/- 3.6 mL . kg . min to 11.3 +/- 4 mL .
kg . min, P = .007 and P = .012, respectively) as well as in VO2/t slope (from
0.35 +/- 0.17 to 0.51 +/- 0.07 mL . kg . min, P = .005). CONCLUSIONS: Peripheral
microcirculation of CHF patients measured by NIRS improved after the
rehabilitation program. NIRS is a noninvasive technique that could be used to
evaluate the effect of rehabilitation on the peripheral microcirculation of CHF
patients.

Langue : ANGLAIS

Tiré à part : OUI