Premature ventricular contractions in acute myocardial infarction. Correlation between their origin and the location of infarction

Summary The purpose of this study was to investigate the correlation between the origin of premature ventricular contractions (PVC's) appearing during acute myocardial infarction (AMI) and the location of the infarction as determined by the electrocardiogram (ECG). The PVCs were termed acute or chronic according to the time of their appearance. The origin of the PVCs, located at the left ventricle (anterior or posterior wall) or the right ventricle, was determined by ECG criteria. In 82 out of 91 cases of acute PVCs (90.2%), the PVCs presented an origin similar to the AMI location (p≤.001). In 23 cases with chronic PVCs, this correlation was not observed. In all 13 cases of primary ventricular fibrillation in which the PVCs origin was determined prior to the event, the PVCs were acute coming from the same location as the AMI. The effectiveness of lidocaine treatment on PVCs was also determined. Out of 44 cases with acute PVCs, 38 responded to lidocaine, with 37 of them showing an origin similar to the AMI location (p≤.001); 5 non-responders showed an origin different from the AMI location. No response was observed in 20 out of 23 cases with chronic PVCs. These results show a good correlation between the origin of the acute PVCs and the location of the AMI. It is concluded that the determination of the origin of PVCs appearing during AMI provides further clinical information as to the location of AMI, its prognosis in relation to serious arrhythmias and the resistance of certain PVCs to lidocaine treatment.