RESUMO
BACKGROUND: Left main coronary artery disease secondary to pulmonary artery compression related to Eisenmenger syndrome is an under-suspected condition that can cause fatal outcomes if left untreated. It presents with typical angina but is frequently mistaken for pulmonary hypertension (PH) symptoms. It is now recognized as one of the few important causes of angina in PH. CASE PRESENTATION: A 37-year-old man with a history of unoperated atrial septal defect and Eisenmenger syndrome came to the outpatient department with a chief complaint of angina on exertion. Electrocardiogram showed regular sinus rhythm with right axis deviation, right ventricular hypertrophy, deep T-wave inversion in inferior and anterior leads suggestive of ischemia or strain, and incomplete right bundle branch block. Cardiac CT showed compression of the left main coronary artery due to a dilated main pulmonary artery. Therefore, this patient was diagnosed with Eisenmenger syndrome with left main compression due to dilated pulmonary artery. He was treated successfully with IVUS-guided stent implantation. The patient experienced marked improvement in regular activities, with no recurrence of angina symptoms. Angiography 3 months after the procedure revealed good patency of the stent, without significant stenosis. CONCLUSIONS: Left main coronary artery compression is a complication that should be suspected in patients with Eisenmenger syndrome presenting with angina symptoms. Non-invasive modalities are recommended for diagnostic evaluation, but the gold-standard technique remains coronary angiography. The best treatment is not well-established, with either myocardial revascularization or PH treatment, but a left main coronary artery stenting procedure is considered an ideal emergent treatment to provide a better quality of life for patients in this condition.