Biofeedback therapy in cardiovascular disease: Rationale and research overview
ABSTRACT
Biofeedback has much therapeutic potential in cardiovascular diseases, since many of these diseases involve dysregulation of the autonomic nervous system. Studies have clearly demonstrated that patients can use biofeedback techniques to regulate the input of the autonomic nervous system to the heart, but the clinical utility of these techniques has not been well explored in systematic trials. Much biofeedback research to date has focused on patients with hypertension, but outcomes have been inconclusive. Preliminary studies suggest that heart rate variability biofeedback may be useful in improving symptoms and quality of life in patients with cardiac disease, and early studies suggest a possible effect of biofeedback on remodeling of the failing heart. Both of these areas require further research, however. Biofeedback is increasingly used as an adjunct to stress management in cardiac rehabilitation programs, providing the impetus for a large-scale, systematic study of self-regulation in cardiac disease.
BIOFEEDBACK AND STRESS MANAGEMENT: AN OPPORTUNITY FOR WIDER IMPACT
As mentioned earlier, biofeedback can serve as a component of stress management programs. Biofeedback is often a very effective adjunct to stress management because it teaches the subject to control physiologic reactions that are part of the stress response and gives the subject feedback to suggest that he or she is adequately practicing relaxation. Biofeedback-mediated stress management may actually be the most practical use of biofeedback in the setting of cardiovascular disease because it is easy to practice and can have an effect on large numbers of patients.
Mental stress has been well documented as a significant risk factor for many forms of cardiovascular disease, and stress management programs have been shown to have an impact on disease progression and symptoms. Many studies, including those reported by Sheps et al for the Psychophysiological Investigations of Myocardial Ischemia (PIMI) study,15 have shown that patients who exhibit ischemia in response to a mental stress test have increased mortality from cardiovascular disease. Jiang and colleagues,16 among others, have shown that mental stress predicts cardiac events in patients with lower ejection fractions, and Blumenthal et al17 have repeatedly demonstrated that stress management training reduces the incidence of wall motion abnormalities in patients with cardiovascular disease. Stress management is included in many cardiac rehabilitation programs, and it is likely that routine use of biofeedback as a component of stress management programs would benefit patients with cardiovascular disease, in whom reproducibly decreasing activation of the autonomic nervous system should be helpful.
According to a recent article in the Heart Advisor, 84% of physicians believe that stress is a risk for cardiovascular disease but only 35% say they feel knowledgeable about stress and a mere 5% feel that they succeed in helping stressed patients.18 Anything that could improve these numbers would be beneficial.
CONCLUSIONS
Cardiovascular conditions in which biofeedback has been shown to be helpful include arrhythmias, hypertension, Raynaud phenomenon, ischemia, infarction, and heart failure, but we have barely begun to explore the potential of biofeedback therapy. Given that many cardiovascular diseases involve inappropriate regulation of the autonomic nervous system, instruction in the use of biofeedback to control activation of the sympathetic and parasympathetic nervous systems is likely to be useful in cardiac patients. Systematic trials are needed.
