Abstract
Acute occlusive myocardial infarction (OMI) complicated by ventricular pre-excitation can present diagnostic challenges. This case describes a 78-year-old male with an 11-h history of chest tightness. A reduction was observed in the extent of localized ventricular pre-excitation, accompanied by secondary ST-T segment abnormalities in leads V1-V3. Emergency coronary angiography revealed occlusion of the left anterior descending artery. This case highlights that a decrease in the extent of local ventricular pre-excitation in R-wave-dominant leads, combined with inference of the accessory pathway location and its potential correlation with the occluded vessel, may facilitate early identification of OMI.