Measurement of heart rate variability during recurrent episodes of ventricular tachyarrhythmia in one patient using wavelet transform analysis

Changes that occur in heart rate characteristics prior to episodes of ventricular tachyarrhythmia (VTA) have been studied previously in an attempt to gain a better understanding as to when these potentially fatal events may occur and to guide potential therapies. In this paper we have the unique opportunity to study the electrocardiogram of one patient over a period of 36 hours, during which multiple VTA episodes occurred. We studied the evolution of the most common heart rate variability (HRV) parameters both prior to and after the onset of the initial VTA. The patient was treated by angiography, ballooning and stenting, and HRV parameters were then studied for a further 24 hours. By studying such patients, a better understanding of the changes occurring in the heart around such VTAs may be gained.