Circannual Variation of Malignant Ventricular Tachyarrhythmias in Patients With Implantable Cardioverter-Defibrillators and Either Coronary Artery Disease or Idiopathic Dilated Cardiomyopathy

• Published in: The American journal of cardiology 1997-05, Vol.79 (9), p.1194-1197
• Main Authors: Fries, MD, Roland P, Heisel, MD, Armin G, Jung, MD, Jens K, Schieffer, MD, Hermann J
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biological and medical sciences; Cardiac arrhythmia; Cardiac dysrhythmias; Cardiology. Vascular system; Cardiomyopathy, Dilated - complications; Cardiomyopathy, Dilated - therapy; Cardiovascular disease; Circadian Rhythm; Coronary Disease - complications; Coronary Disease - therapy; Death, Sudden, Cardiac; Defibrillators, Implantable - adverse effects; Female; Follow-Up Studies; Heart; Humans; Incidence; Male; Medical equipment; Medical sciences; Middle Aged; Recurrence; Regression Analysis; Seasons; Stress, Physiological - etiology; Tachycardia, Ventricular - epidemiology; Tachycardia, Ventricular - etiology; Temperature; Transplants & implants
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/S0002-9149(97)00081-7

We studied the possible relation between the frequency of ventricular tachyarrhythmic events and thermal stress in patients with an implantable cardioverter-defibrillator (ICD) living in a locally limited area under homogeneous climatic conditions. The frequency of tachyarrhythmic events was correlated with the thermal stress level according to the “Klima Michel Model,” a complete thermophysiologic model that calculates “felt-temperature” values on the basis of the outdoor temperature and further meteorologic data. During a mean follow-up time of 40 ± 17 months (range 4 to 72), 761 ventricular tachyarrhythmic events occurred in 50 of 138 consecutive ICD recipients. Analysis of the monthly felt-temperature levels and the mean circannual variation of the registered ventricular arrhythmias suggested that very cold and very hot conditions may be associated with an increased frequency of ventricular tachyarrhythmias. This finding was confirmed by calculation of the sum of tachyarrhythmias on all 2,039 days of the follow-up period divided into 5-degree-step felt-temperature classes. Thus, thermal stress may be 1 factor triggering the occurrence of ventricular tachyarrhythmias in patients with cardiac disease and suppressed cardiac function. Part of the increase in cardiac mortality under above-average hot and cold atmospheric conditions may be attributed to ventricular arrhythmic events.