Late Gadolinium Enhancement on Cardiac Magnetic Resonance Imaging in Acute Myocardial Infarction Due to Myocardial Bridging: A Clinical Dilemma

A 51-year-old male with a family history of premature coronary artery disease (CAD) presented with acute myocardial infarction (AMI) with coronary angiography demonstrating no angiographic disease and a mid-left anterior descending (LAD) myocardial bridging (MB) segment with 71% mean lumen diameter (MLD) compression. Due to continually rising biomarkers and recurrent angina, cardiac magnetic resonance imaging(CMR) was obtained demonstrating late gadolinium enhancement (LGE) involving the mid-distal LAD territory. Patient subsequently underwent successful percutaneous coronary intervention (PCI) with drug-eluting stent (DES) to the MB segment with resolution of symptoms, which persisted over a year. MBis defined as an intramuscular segment resulting in overlying bands of myocardium, also called "tunneled" artery. Once thought benign, MB has been reported to cause unstable angina, AMI, life-threatening arrhythmias, and sudden cardiac death. PCI has been reported to relieve symptoms balanced against rates of in-stent restenosis and target lesion revascularization as high as 19% with DES. This case illustrates the utility of CMR in the setting of AMI to guide decision to purse PCI in symptomatic MB.