This 48-year-old man with a history of untreated hyperlipidemia and smoking presented to the Emergency Department with severe anterior chest pain for the past 70 minutes: 

• Sinus rhythm with marked sinus arrhythmia
• Inferior myocardial infarction, acute

This ECG was recorded ten minutes later, immediately before the patient was transferred to Cardiac Catheterization Laboratory for coronary angiography. The right chest leads were recorded: Lead V2 – V1 – V3R to V6R:

• The right-side chest leads have been recorded
• Sinus rhythm
• Acute inferior infarction, acute right ventricular infarction

Coronary angiography demonstrated a complex ulcerated plaque with 90% stenosis in the middle segment of the right coronary artery. The lesion was dilated and stented, with excellent results, and the patient became free of chest pain. The following ECG was recorded approximately 1.5 hours after after angioplasty and stenting of the right coronary artery:

• Sinus rhythm, inferior infarct
• Compared with the previous tracing, there has been resolution of the ST elevation in II, III, aVF
• Negative T waves are present in III and aVF, suggestive of inferior ischemia