Fluoroscopic “Calcium Sign” or Reverse “C” Sign of the Aortic Knuckle in a Case of Chronic Total Occlusion of Left Anterior Descending Coronary Artery

We describe an interesting fluoroscopic calcification of the aortic knuckle assuming a reverse “C” shape in an atherosclerotic aorta in a 42‑year‑old male presenting with anterior wall ST‑elevation myocardial infarction with dyslipidemia. Although calcification of the aortic knuckle and dilatation of the aorta is a common phenomenon in the elderly population, otherwise known as the “unfolding of aorta,” we observed this interesting pattern of calcification in a middle‑aged person in an atherosclerotic aorta with calcification. The patient had double‑vessel coronary artery disease with chronic total occlusion in the left anterior descending coronary artery and significant stenosis in the mid‑segment of the right coronary artery, which we revascularized with drug‑eluting stents and achieved TIMI III flow. Although calcium sign or C sign is described in aortic dissection and it is not specific to it, we observed this interesting pattern of calcification in a middle‑aged person in the atherosclerotic aorta with dyslipidemia.