Heart Rate Turbulence

Heart Rate Turbulence

HRT - Heart Rate Turbulence - is the physiological, bi-phasic response of the sinus node to premature ventricular contractions. It consists of a short initial acceleration followed by a deceleration of the heart rate. HRT can be quantified by two numerical parameters, namely the Turbulence Onset and the Turbulence Slope. The underlying mechanisms of HRT have not been fully identified. HRT is most probably an autonomous baro-reflex. The premature ventricular contraction causes a brief disturbance of the arterial blood pressure (low amplitude of the premature beat, high amplitude of the ensuing normal beat). When the autonomic control system is intact, this fleeting change is registered immediately with an instantaneous response in the form of HRT. If the autonomic control system is impaired, this reaction is either weakened or entirely missing.

HRT is suitable for assessing the risk following myocardial infarction. After analysis of the data of more than 3,000 post-infarction patients it was established that HRT is - independent of other risk predictors - the most powerful ECG-related risk predictor. The predictive value of HRT is comparable with that of the ejection fraction of the left ventricle.

Visual Presentation

In HRT-Demo_Java or HRT-Demo_JavaScript you will find a visual presentation of the Heart Rate Turbulence. However, since this visualization requires your browser to support Java applets or Javascript. All 4th generation browsers (i.e. Netscape 4.x or Internet Explorer 4.x) with Java- or Javascript-support being activated in the preferences panel are able to show this demonstration. In case of missing 4D-displays, please check your browser settings or contact your system operator.