[Analysis of the preceding R-R interval and the coupling interval on premature ventricular contractions]

Premature Ventricular Contractions (PVCs) are one of the common arrhythmias. Although the analysis of the preceding R-R interval and the coupling interval on the Holter electrocardiogram, the Lorenz plotting method, has been used to characterize mature of PVC, this analysis has typically been performed without regard to the morphological classification of the electrocardiogram waveforms. Therefore, we performed the Lorenz plotting after a PVC classification. We analyzed 45 cases with more than 1,000 PVCs per day. Twenty-six of the cases with PVCs had no organic heart disease (idiopathic PVC); nineteen of the cases with PVCs had organic heart disease (PVC with disease). Each R-R interval was analyzed after classification based on the morphology of each QRS wave of the PVC. The computer generated a two-dimensional plot of the relationship between the preceding R-R interval of PVC and the following coupling interval. The forms of PVCs were monoform in idiopathic PVC and were mostly multiform in PVC with disease. The patterns on Lorenz plotting in idiopathic PVC had a tendency to be uniform with small standard deviations. In contrast, multiform PVCs tended to be highly variable with large standard deviations. The value of SD was 32.1 +/- 12.0 msec in idiopathic PVC, and that of the slope "a" was 0.048 +/- 0.051 in PVC with disease. Using the SD values and the slope "a" values, we were able to classify idiopathic PVC vs. PVC with disease with a 95% sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)