Abstract
BACKGROUND: Despite successful revascularization, a significant number of patients with obstructive coronary artery disease continue to experience angina because of often-overlooked coronary microvascular dysfunction (CMD). CASE SUMMARY: A 46-year-old man with hypertension, hyperlipidemia, and alcohol use presented with angina and left main stenosis; despite revascularization, symptoms and abnormalities on optical pumped magnetometer magnetocardiography (OPM-MCG) persisted, and AccuIMR (angiography-derived index of microcirculatory resistance) supported a diagnosis of CMD. Nicorandil led to complete symptom resolution with normalization of OPM-MCG. DISCUSSION: CMD may accelerate stenosis progression and exacerbate ischemia in coronary artery disease, and OPM-MCG provides a sensitive noninvasive tool to capture these changes. TAKE-HOME MESSAGES: This case demonstrates that CMD should be actively assessed in patients with hemodynamically significant stenosis, even after successful revascularization. OPM-MCG enables dynamic, noninvasive detection of ischemic changes, making it suitable for longitudinal follow-up and management in patients after percutaneous coronary intervention.