Analysis of the onset and termination of repeated pattern ventricular arrhythmias

A group of algorithms has been developed to investigate the characteristics of beat-to-beat intervals preceding and following the onset and termination of repeated pattern ventricular arrhythmias (RPVA) such as bigeminy and trigeminy. Eighty-five patients, each with more than 3000 ventricular ectopic beats in a 24-hour Holter recording and with more than 10 episodes of RPVA, were evaluated. A statistically significant prolongation of sinus intervals preceding the onset of bigeminy and trigeminy and shortening of postectopic intervals after the onset were observed. In addition, shortening of postectopic intervals before the termination of bigeminy and trigeminy and lengthening of sinus intervals following their termination were also seen. A significant presence of these characteristics was not observed in arrhythmias with a greater number of sinus beats between ectopic beats. These dynamics provide information which may be utilized in the assessment of mechanisms involved in the onset and termination of RPVA.