Acute changes in ambient temperature are associated with adverse changes in cardiac rhythm

作者：Wasserman Erin B; Zareba Wojciech; Utell Mark J; Oakes David; Hopke Philip K; Frampton Mark; Chalupa David; Beckett William; Rich David Q^*

来源：Air Quality, Atmosphere and Health, 2014, 7(3): 357-367.

DOI：10.1007/s11869-014-0244-0

• Ambient temperature
• Cardiac rehabilitation
• Heart rate variability
• Repolarization

Both increases and decreases in ambient temperature have been associated with increased cardiovascular mortality and morbidity. However, the mechanism(s) remain unclear. We examined associations between biomarkers of pathways thought to, in part, explain these associations and changes in ambient temperature in a panel of predominantly postmyocardial infarction or poststent patients. We studied 76 subjects who had a recent coronary event and were participating in a cardiac rehabilitation program. In these patients, we measured heart rate variability, repolarization, and baroreflex sensitivity parameters using Holter ECG recordings before and during supervised, graded, twice-weekly, exercise sessions. Hourly temperature measurements were made at a monitoring site near the rehabilitation center. Using linear mixed models, we observed decreases in square root of the mean of the sum of the squared differences between adjacent NN intervals (rMSSD) and deceleration capacity, associated with increases in ambient temperature in the previous 4 days. Additionally, decreased rMSSD was associated with both increasing temperature (mean in previous 6 h) in the summer and decreasing temperature (mean in the previous 3 weeks) in the winter. In a panel of cardiac rehabilitation patients, changes in ambient temperature were associated with decreases in markers of heart rate variability and baroreflex sensitivity, which may lead to increased risk of arrhythmic events and sudden death in postinfarction patients.

• 出版日期2014-9