Inotropic agents improve the peripheral microcirculation of patients with end-stage chronic heart failure

Skeletal muscle microcirculation impairment in patients with chronic heart failure (CHF) seems to correlate with disease severity. We evaluated the microcirculation by near-infrared spectroscopy (NIRS) occlusion technique before and after inotropic infusion.

We evaluated 25 patients with stable CHF, 30 patients with end-stage CHF (ESCHF) receiving treatment with intermittent infusion of inotropic agents, and 12 healthy subjects. Thenar muscle tissue oxygen saturation (StO(2)%) was measured noninvasively by NIRS before, during, and after 3-minute occlusion of the brachial artery (occlusion technique) in all subjects and in patients with ESCHF before and after 6 hours of inotropic infusion (dobutamine and/or levosimendan) or placebo (N = 5).

Patients with ESCHF or CHF presented significantly lower StO(2)% than healthy subjects (74.5% +/- 7%, 78.6% +/- 6%, and 85% +/- 5%, respectively; P = .0001), lower oxygen consumption rate during occlusion (24.6% +/- 8%/min, 28.6% +/- 10%/min, and 38.1% +/- 11.1%/min, respectively; P = .001), and lower reperfusion rate (327% +/- 141%/min, 410% +/- 106%/min, and 480% +/- 133%/min, respectively; P = .002). After 6 hours of inotropic infusion, patients with ESCHF showed significantly increased StO(2)% (74.5% +/- 7% to 82% +/- 9%, P = .001), oxygen consumption rate (24.6% +/- 8%/min to 29.3% +/- 8%/min, P = .009), and reperfusion rate (327% +/- 141%/min to 467% +/- 151%/min, P = .001). No statistical difference was noted in the placebo group.

Peripheral muscle microcirculation as assessed by NIRS is impaired in patients with CHF. This impairment is partially reversed by infusion of inotropic agents in patients with ESCHF.