Post-surgical External Coronary Artery Compression: A Rare Cause of ST Elevation Myocardial Infarction

Iatrogenic ST elevation myocardial infarction (STEMI) after aortic valve surgery is a rare complication. Myocardial infarction (MI) due to mediastinal drain tube compression on the native coronary artery is also seen rarely. We present a case of ST elevation inferior myocardial infarction due to post-surgical drain tube placed after aortic valve replacement compressing on the right-sided posterior descending artery (rPDA). A 75-year-old female presented with exertional chest pain and was found to have severe aortic stenosis (AS). After a normal coronary angiogram and proper risk stratification, the patient underwent surgical aortic valve replacement (SAVR). One day after surgery in the post-operative area, the patient was complaining about central chest pain suggestive of anginal pain. Electrocardiogram (ECG) revealed that she has ST elevation myocardial infarction in the inferior wall. Immediately, she was taken to the cardiac catheterization laboratory, which revealed that she has occlusion of the posterior descending artery due to compression by a post-operative mediastinal chest tube. All features of myocardial infarction resolved after simple manipulation of the drain tube. The compression of the epicardial coronary artery after aortic valve surgery is very unusual. There are a few cases of other coronary artery compression due to mediastinal chest tube, but posterior descending artery compression causing ST elevation inferior myocardial compression is unique. Though rare, we need to be vigilant about mediastinal chest tube compression, which can cause ST elevation myocardial infarction after cardiac surgery.