Problem: Each year, 1.1 million Americans experience acute myocardial infarction (AMI). Diminished heart rate variability (HRV) is an important predictor of morbidity and mortality in this population. Another major determinant of negative outcomes is the extent of myocardial damage, which is influenced by factors impacting myocardial oxygen (MVO2) supply and demand. Previous research has shown that relaxing music reduces anxiety, improves MVO2 supply-to-demand ratios and increases HRV. Intervention issues including frequency and optimal time of day for music have not been tested. Therefore, the purpose of this randomized six-group experimental design study was to compare effectiveness of relaxing music, rest, and treatment as usual, for improving indicators of cardiac autonomic nervous system function and reducing anxiety. Conceptual Framework: The conceptual framework guiding this study is based on the premise that if music can elicit a relaxation response, the stress response will be broken. Methods: The six comparison groups were (1) music once per day (morning); (2 & 3) music twice per day (morning & afternoon; morning & evening); (4) music three times per day (morning, afternoon, & evening); (5) attention (quiet rest); and (6) control (usual treatment). Dependent variables included heart rate, respiratory rate, blood pressure, MVO2 demand (rate pressure product), HRV, and state anxiety. Results: One hundred eighty individuals who experienced AMI during the previous 72 hours participated. Analysis of variance was used to compare change scores of dependent variables. Tukey’s post hoc tests revealed significant improvements for all dependent variables in music group participants at each intervention time. Conclusion: Relaxing music sessions promote a relaxation response during recovery from AMI, thereby reducing MVO2 demand and potentially reducing the extent of myocardial injury and damage and improving measures of HRV. Recommendations for implementing relaxing music sessions will be presented. This study was funded in part by NINR 5R01NR005004-06.
Session #1213 - Cardiovascular Interventions and Outcomes
The 29th Annual MNRS Research Conference (April 1-4, 2005)