RSA-Biofeedback reduce depressive symptoms in cardiac surgery patients

The present study examined the potential efficacy of Respiratory Sinus Arrhythmia (RSA)-biofeedback training in increasing RSA in first-time cardiac surgery patients. RSA is a widely used measure of vagal tone modulation. Therefore, reduced RSA represents an index of poor vagal control and may represent a marker of cardiovascular risk, being predictive of morbidity in patients with cardiovascular diseases. Furthermore, reduced RSA may be linked to depression and/or depressive symptoms, also considered risk factors for cardiovascular disease. The present study intended to verify whether patients after cardiac surgery would be able to increase vagal control after RSA-biofeedback training and to clarify whether an increase in cardiac vagal tone would be associated with a depressive symptoms reduction. 26 consecutive patients who underwent first time cardiac surgery were enrolled in the study. Patients were randomly assigned to the RSA-biofeedback plus standard rehabilitation group (N = 13) or to the standard rehabilitation group (N = 13). All the patients underwent pre- and post-training assessments, which included, RSA recording at rest and depressive symptoms evaluation [assessed with the Center for Epidemiological Study of Depression, (CES-D)]. The RSA-biofeedback training consisted of five 45 min daily sessions. During each RSA-biofeedback training session, patients were instructed to maximize their RSA. Patients who underwent RSA-biofeedback plus standard rehabilitation showed significant RSA increase from pre- to post-training, and significantly higher post-training RSA compared to patients in standard rehabilitation group. Patients who underwent RSA-biofeedback plus standard rehabilitation, also showed a significant reduction in depressive symptoms from pre- to post-training. Furthermore, changes in RSA were inversely associated to changes in CES-D scores from pre- to post-training. These findings add to the literature on the biobehavioral treatment of cardiovascular diseases by showing that the effectiveness of RSA-biofeedback training for increasing vagal modulation extends to patients after cardiac surgery. In particular, RSA-biofeedback was effective in increasing cardiac vagal control and reducing depressive symptoms. These preliminary findings may extend the RSA-biofeedback effectiveness to post-surgical rehabilitation and suggest that this training may add to the efficacy of cardiac rehabilitation protocols and postoperative programs on risk reduction.