Circadian variation of heart rate is affected by environment: a study of continuous electrocardiographic monitoring in members of a symphony orchestra.

Abstract

Twenty four hour ambulatory ST segment monitoring was performed on 48 members (43 players and five members of the management/technical team) of the British Broadcasting Corporation (BBC) symphony orchestra without a history of cardiac disease. This period included final rehearsals and live performances (for audience and radio) of music by Richard Strauss and Mozart at the Royal Festival Hall (n = 36) and Rachmaninov and Tchaikovsky at the Barbican Arts Centre (n = 21). During the period of monitoring one person (2%) had transient ST segment changes. Mean heart rates were significantly higher during the live performances than during the rehearsals. Mean heart rates during the live performance of Rachmaninov and Tchaikovsky were significantly higher than during Strauss and Mozart in those (n = 6) who were monitored on both occasions. Mean heart rates in the management and technical team were higher than those of the players. The recognised circadian pattern of heart rate, with a peak in the morning waking hours, was altered similarly during both concert days, with a primary peak occurring in the evening hours and a lesser peak in the morning for both musicians and management/technical staff. This study showed that environmental factors are of primary importance in defining the circadian pattern of heart rate. This has important implications when identifying peak periods of cardiovascular stress and tailoring drug treatment for patients with angina pectoris.

Should we get up in the morning? Observations on circadian variations in cardiac events.

“…'6 Though blood pressure begins to rise before waking the major surge results from the start of daily activities. '3 Finally, members of a symphony orchestra who had an unusual temporal pattern of work showed significant alterations in the cir- 20 cadian pattern of heart rate, which presumably reflects similar changes in catecholamine release and blood pressure. Because most people get up in the morning it is difficult to study circadian patterns in cardiac disease.…”

Diurnal Heart Rate Patterns in Inappropriate Sinus Tachycardia

“…The parasympathetic nervous system seems to exhibit a true circadian variation with gradual withdrawal during the daytime 17 . The sympathetic system is activated during the morning hours and is influenced by posture, waking, activity and environmental stress 18–20 …”

“…Diabetics with autonomic neuropathy, despite enhanced sympathetic tone and high resting heart rates, also maintain some degree of circadian variation in heart rates, although blunted 4,22 . Activity and stress can increase daytime heart rates, but the diurnal drop in heart rate is still observed 20 . Low sympathetic states such as daytime reclining are associated with a decreased diurnal variation in heart rate.…”

“…17 The sympathetic system is activated during the morning hours and is influenced by posture, waking, activity and environmental stress. [18][19][20]…”

European Survey on Circadian Variation of Angina Pectoris (ESCVA) in Treated Patients

“…The concurrent change of activity is, perhaps, again associated with physiological changes leading to a decreased angina pectoris threshold. The influence of environmental change and stress on physiological changes has also been demonstrated in an unusual model involving electrocardiographic monitoring in members of a symphony orchestra during performance [19].…”