Case Report: Delayed diagnosis: a case of left main coronary artery spasm

Left main coronary artery (LMCA) spasm is an exceedingly rare but potentially fatal condition. We present a case of severe stenosis of LMCA found by coronary angiography (CAG) due to recurrent chest pain, and subsequently received coronary artery bypass grafting (CABG). Nine years later, the patient was readmitted to the hospital because of precordial discomfort. During hospitalization, CAG was performed once again and showed no significant stenosis in the LMCA, leading to the diagnosis of LMCA spasm. This case emphasizes to interventional cardiologists the critical need to consider the possibility of LMCA spasm when diagnosing LMCA lesions. It highlights the importance of thorough and proactive pretreatment and comprehensive clinical judgment to minimize the risk of misdiagnosis.