Aim: To investigate the association of a single ventricular ectopic beat with physical, emotional, or meteorologic stress and the role of age, sex, antiarrhythmic and other medicament therapy and participant characteristics.
Methods: The study included 457 participants who were consecutively assigned to undergo continuous 24-hour Holter monitoring and who completed a structured questionnaire about their physical activity and mental stress. Multiple regression analysis of data on 11 meteorologic parameters, participants' baseline characteristics, and medications they used was performed for subgroups according to sex and age, with 65 years as age limit.
Results: Wind speed, low relative humidity, increasing relative humidity, and emotional stress were independent predictors of ventricular ectopic beat, whereas warm front passage showed a protective effect in all participant subgroups (P<0.05 in all cases). Physical activity was an independent predictor of ventricular ectopic beat in women (P=0.02) and cold front passage in men P=0.003). The circadian variation in frequency of ventricular ectopic beats persisted in all subgroups after adjustments for external triggers (P<0.001 in all cases). Among chronic risk factors, familial background and previous myocardial infarction were independent predictors of ventricular ectopic beat in men and younger (P<0.05 in all cases). Nitrates (P<0.03 in all cases) and angiotensin converting enzyme inhibitors (P<0.02 in all cases) exerted protective effect in younger participants as well as did beta-blockers in the elderly (P<0.003 in all cases).
Conclusion: In addition to existence of an endogenous, external triggering-independent circadian pattern, physical, emotional, and meteorologic stress may act as triggers of ventricular ectopic beat in a manner that differs from triggering more complex arrhythmias. Familial background seems to have a significant impact on arrhythmogenesis in men.