BIOFEEDBACK CAN BENEFIT HEART FAILURE PATIENTS, STUDY FINDS
COLUMBUS, Ohio -- People with advanced heart failure can increase blood flow to their organs by using a relatively simple biofeedback-relaxation technique, a recent study suggests.
Researchers compared 25 heart failure patients who completed a 20-minute biofeedback-relaxation program and 15 who simply rested quietly for 20 minutes. They found that those in the biofeedback-relaxation group had significantly greater cardiac output and blood vessel dilation at the end of the program than those who simply rested quietly.
"Our results are preliminary, but they do show that a single session of biofeedback-relaxation produced at least temporary help for patients with advanced heart failure," said Debra K. Moser, assistant professor of nursing at Ohio State University and lead author of the study.
"This therapy has a lot of potential. We think that it might help people with heart failure remain more medically stable and increase their feelings of control. If it could contribute
to decreasing vessel constriction, decreasing sympathetic nervous system activation and increasing cardiac output, that would be wonderful. Thats a major thrust of the drug therapy that heart failure patients undergo."
In heart failure, which affects more than 2.5 million Americans, the heart is unable to pump enough blood efficiently to provide blood supply to tissues and organs. In addition, vessels constrict to increase blood pressure and improve oxygen delivery to the organs. While these changes initially improve bloodflow, they continue unchecked and ultimately result in severe vessel constriction and increased resistance to cardiac pumping, which leads to further loss of pumping efficiency and inadequate blood and oxygen supply to the organs.
Moser conducted this research with Kathleen Dracup, professor of nursing, and Mary A. Woo, assistant professor of nursing, both from UCLA, and Lynne W. Stevenson, associate professor of nursing at Harvard Medical School. The groups work was published in a recent issue of the journal Alternative Therapies.
For their study, Moser and her colleagues randomly assigned 40 heart failure patients to two groups. Patients assigned to the first group completed a 20-minute biofeedback-relaxation program; those assigned to the second rested quietly for 20 minutes. Before and after the 20-minute session, the researchers measured each patients skin temperature, cardiac output, vascular resistance and cardiac pressures, adrenaline level, oxygen consumption, fluid build-up and respiratory rate.
For the biofeedback-relaxation sessions, the researchers attached skin temperature sensors to the patients fingers and feet. The sensors displayed skin temperature data so that the patients could see it. The researchers then told the patients to increase their skin temperature -- an indirect measure of improved blood flow. To accomplish this, they told the patients to imagine their blood vessels relaxing and to imagine a particular situation or activity that represented hand warmth and relaxation. The researchers also guided the patients through a brief session of progressive muscle relaxation, which has been shown to increase blood vessel dilation.
There were no significant medical differences between the patients in the two groups before the 20-minute intervention. However, immediately after the intervention, the patients in the biofeedback-relaxation group had significantly greater skin temperature (averaging about 4 degrees higher) and cardiac output (about 0.3 liters per minute more), as compared with their quietly resting counterparts. Also, biofeedback-relaxation patients had a significantly lower respiratory rate (17 breaths per minute compared to 25 breaths per minute for the resting group).
"The ability of biofeedback-relaxation to decrease respiratory rate may be clinically useful in patients with advanced heart failure, for whom feelings of breathlessness are common and troublesome," Moser said.
Further studies are needed to document the effect of biofeedback-relaxation on heart failure patients, Moser said.
"For biofeedback to be effective in the long-term, people need to learn it in a six- to 10-week program and then practice it every day," Moser said. "However, this preliminary evidence suggests that advanced heart failure patients, who are very sick, can do biofeedback-relaxation successfully and possibly experience some improvements."
Moser is currently studying the effects of a six-week biofeedback-relaxation program on the year-long health status of advanced heart failure patients.
"I think were going to find that biofeedback-relaxation gives heart failure patients an added benefit, that it produces some low level of vasodilation that we think will help patients maintain a more steady state," Moser said. "Even relatively minor degrees of sustained vasodilation could be advantageous in patients with heart failure."
Contact: Debra K. Moser, (614) 292-4746; Moser.45@osu.edu
Written by Kelly McConaghy Kershner