Complementary CT Coronary Angiography after Negative Selective Coronary Angiography

Abstract

A 53-year-old male was admitted for typical acute chest pain. The ECG showed a mirror image of posterior myocardial ischemia. Initial biology was normal but cardiac markers (creatine kinase and troponin) rose later. Echocardiography did not reveal any hypokinetic myocardial segment. There was no left ventricular dysfunction or valvular disease. There was no pericardial effusion or aortic dissection image. This patient was treated as a "non-ST segment elevation myocardial infarction" (NSTEMI), also called subendocardial myocardial infarction. A selective coronary angiography (SCA) was performed the next day and after careful examination by several experts, no coronary lesion was detected. Left ventriculography was also normal. Cardiac MRI was then performed and revealed a late focal subendocardial enhancement, located in the mid infero-posterior myocardial segment (Fig. A, arrow). This lesion appeared to be ischemic, despite normal SCA. Computed tomography coronary angiography (CTCA) was finally done, showing a hypodense image, with also an ischemic aspect, in the same subendocardial area (Fig. B, arrow) as observed on MRI. Furthermore, CTCA detected tight luminal narrowing with hypodense material (soft atheroma or clot) in a circumflex branch (Fig. C, arrow), corresponding to the suspected ischemic territory. In this case, CTCA both confirmed ischemic etiology and identified culprit artery missed by SCA. CommentSCA is the gold standard for investigating coronary arteries. This invasive technique gives precise information about coronary stenosis and can be immediately extended to a therapeutic approach if necessary. However, SCA can miss diagnosis in some cases such as ostial stenosis of the left main trunk, abnormal coronary origin or as demonstrated