Heart Rate Turbulence: A New Predictor for Risk of Sudden Cardiac Death
Authors: Johnson Francis1; Mari A. Watanabe2; Georg Schmidt3
Source: Annals of Noninvasive Electrocardiology, Volume 10, Number 1, January 2005 , pp. 102-109(8)
Publisher: Blackwell Publishing
Abstract:
Initial acceleration and a subsequent deceleration of sinus rhythm following a ventricular ectopic beat with a compensatory pause has been termed heart rate turbulence (HRT). The changes in sinus rhythm are thought to be mediated by a baroreflex response to the lower stroke volume of the ectopic beat. HRT is vagally mediated and abolished by atropine, whereas
-blockers have no effect. HRT has been shown to be an independent and powerful predictor of mortality after myocardial infarction. In patients on
-blockers, it scores better than left ventricular ejection fraction (LVEF) in its predictive value. Two common measures of HRT are turbulence onset and turbulence slope. When both these measures are abnormal, it is as powerful a predictor of mortality as LVEF. HRT correlates with other indices of cardiac autonomic functions like baroreflex sensitivity and heart rate variability. A composite autonomic index including all these three has been shown to be a powerful predictor of mortality. In patients undergoing direct percutaneous intervention for myocardial infarction, HRT improves in those attaining successful reperfusion. Abnormal values for HRT have been noted in patients with dilated cardiomyopathy and Chagas disease. Diabetic and elderly individuals are more likely to have blunted HRT. HRT cannot be measured in patients lacking ventricular ectopic beats and in patients presenting with atrial fibrillation.A.N.E. 2005;10(1):102109
Keywords: heart rate turbulence; sudden death; autonomic response
Document Type: Research article
DOI: 10.1111/j.1542-474X.2005.10102.x
Affiliations: 1: Medical College Calicut, Kerala, India 2: Department of Pharmacological and Physiological Science, St. Louis University, St. Louis, MO 3: 1. Medizinische Klinik der Technischen Universität München, München, Germany

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