A Case of Acute Myocardial Infarction with Myocardial Damage Caused by Thrombi Originally Located in the Non-culprit Lesion

Distal thromboembolism can develop in patients with acute myocardial infarction, but is rare in non-culprit lesions. Here, we report a case of acute myocardial infarction in which myocardial damage may have been caused by thrombi originally located in the non-culprit lesion. An 81-year-old woman presented with back pain and was diagnosed with ST-segment elevation acute myocardial infarction. Emergency coronary angiography demonstrated total occlusion in the mid-portion of the left anterior descending coronary artery and severe stenosis in the mid-portion of the right coronary artery. Collateral flow to the right coronary artery from the first septal perforator of the left anterior descending coronary artery, which branched before the total occlusion of the left anterior descending coronary artery, was observed. After recanalization of the left anterior descending coronary by thrombus aspiration, thrombi originally located in the right coronary artery migrated to the distal part. Myocardial imaging with thallium-201 and technetium-99m-pyrophosphate showed damaged but viable myocardium in the inferior wall of the mid-left ventricle.