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Ventricular premature complexes (VPC) are identified as premature wide QRS complexes, usually with no preceding P waves. Normal sinus P wave may precede a late diastolic VPC. Such a VPC may be mistaken for intermittent WPW (pre-excitation) syndrome. Coupling interval is the interval from the onset of the preceding QRS complex to the onset of the VPC. VPCs with same morphology (monomorphic) having the same coupling interval are thought to arise from a single focus (unifocal). Monomorphic VPCs with varying coupling interval can occur in parasystole. In parasystole, the ectopic focus is protected from the sinus impulses by an entrance block. In case of parasystole, the interectopic intervals have a simple numerical ratio. VPCs with different coupling interval and different morphologies are known as multifocal VPCs. Multifocal VPCs may be the harbringer of more complex ventricular tachyarrhythmias. In this case The first three VPCs in the rhythm strip have the same coupling interval of around 400 msec and appear to have the same morphology while the fourth one has a longer coupling interval of about 600 msec and has as slightly different morphology. The VPCs captured in the standard leads show an LBBB like morphology suggesting a right ventricular origin. The QRS complexes are predominantly negative in inferior leads. The usual benign ectopics originating from the right ventricular outflow tract (RVOT) have positive QRS complexes in inferior leads as the activation proceeds from above downwards. Here it is the reverse pattern suggesting possibly origin from the right ventricular apical region. The discordant ST – T changes (ST depression and T wave inversion in leads with a dominant positive QRS and vice versa) are usually seen in VPCs because the difference in depolarization sequence compared to the sinus beat also changes the repolarization sequence.