Unexpected evolution of a non-stenotic lesion in the left main coronary artery of a patient with non-ST-segment elevation myocardial infarction

A 72-year-old man was referred to our catheterization laboratory 48 hours after a non-ST-segment elevation myocardial infarction. His medical history included coronary artery disease (CAD) (percutaneous coronary intervention of the right coronary artery and chronic total occlusion of the circumflex artery), atrial fibrillation (AF), and chronic kidney disease. An electrocardiogram showed a pre-existent left bundle-branch block and the patient's maximum cardiac troponin concentration was 8.64 µg/L (upper limit of normal: 0.003 µg/L). The coronary angiogram revealed an ulcerated plaque of the left main coronary artery (LMCA) and moderate stenosis of the left anterior descending (LAD) coronary artery. A non-interventional approach to treatment was chosen. One month later, a control angiography showed a giant distal aneurysm complicating the lesion; the fractional flow reserve (FFR) value in the LAD was 0.74. The heart team discussed the case and concluded that the aneurysm was inaccessible via surgery. To protect the LAD from possible covered stent thrombosis or restenosis, coronary artery bypass grafting of the LAD was performed prior to percutaneous coronary intervention (PCI). Five days later, we proceeded with percutaneous exclusion of the aneurysm. We combined coil embolization of three Interlock™ two-dimensional detachable coils with stenting of the LMCA, using a PK Papyrus™ covered stent. Effective angiographic exclusion was achieved. The patient was discharged on warfarin, aspirin, and clopidogrel for 1 month, followed by long-term aspirin and oral anticoagulation. A 6-month follow-up angiography demonstrated a completely sealed aneurysm and optical coherence tomography (OCT) confirmed the successful endothelialization of the covered stent.