COMPARISON OF QTC INTERVAL, QRS DURATION AND JTC INTERVAL TO PREDICT REPOLARISATION ABNORMALITY IN INTRA-VENTRICULAR CONDUCTION DISTURBANCE PATIENTS – A STUDY CONDUCTED IN MEDICAL COLLEGE KOLKATA

Abstract

Introduction: Disturbances of intra-ventricular conduction are associated with distinct ECG abnormalities inpatients and QTc interval is found to be prolonged which may be interpreted as higher arrhythmogenic property of such patients. But the repolarisation time of such patients are more or less same which isexpressed by JTc interval. In this study, it is found that JTc interval measurement is more significant thanQTc interval in IVCD patients as predictor of cardiac arrhythmogenesis

Methodology: Institution based observational, cross sectional study among 100 patients attending cardiology OPD for a period of approximate 2 years with diagnosis of different IVCDs ( RBBB, LBBB, BFB) on surface ECG .QRS, QTc, JTc interval were measured .

Result: Mean QRS and QTc value were more for LBBB group as compared to RBBB and BFB group. But corrected JTc value was more or less equal in three groups. Post HOC analysis showed that there was no significant correlation of JTc interval between all the three groups. JTc interval was not found to be statistically significant indicating that repolarisation abnormality is minimum in both RBBB, LBBB and BFB group

Conclusion: JTc interval is not significantly high in LBBB patients indicating long QTcin LBBB is due to depolarization abnormality rather than repolarisation abnormality and not a predictor of arrhythmogenesis.