Voluntary Control of Vascular Tone by Using Skin-Temperature Biofeedback-Relaxation in Patients with Advanced Heart Failure

This randomized, controlled study conducted at the University of California, Los Angeles, tested the ability of biofeedback/relaxation training to produce vasodilation and enhance cardiac output in 40 patients with advanced heart failure. Patients were randomly assigned to one of two groups: the intervention group received one session of skin-temperature biofeedback with imagery and progressive muscle relaxation; the control group was given no instruction in biofeedback/relaxation techniques. All patients were tested at baseline for various physiological measures. The intervention group showed a variety of positive changes including increase in skin temperature of the finger and foot, increase in cardiac output, decrease in systemic vascular resistance, and decrease in respiratory rate. None of these changes were observed in the control group. Neither group showed changes in oxygen consumption or catecholamine levels. The study showed that in addition to local changes (increase in skin temperature), the biofeedback-relaxation treatment produced effects on a system-wide level.