|Year : 2021 | Volume
| Issue : 4 | Page : 124-127
Fluoroscopic “calcium sign” or reverse “c” sign of the aortic knuckle in a case of chronic total occlusion of left anterior descending coronary artery
Debasish Das, Abhinav Kumar, Jogendra Singh, Subhas Pramanik
Department of Cardiology, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
|Date of Submission||27-Sep-2021|
|Date of Decision||03-Dec-2021|
|Date of Acceptance||18-Dec-2021|
|Date of Web Publication||03-Feb-2022|
Dr. Debasish Das
Department of Cardiology, All India Institute of Medical Sciences, Bhubaneswar - 751 019, Odisha
Source of Support: None, Conflict of Interest: None
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.
Keywords: C sign, calcium sign, chronic total occlusion, left anterior descending coronary artery
|How to cite this article:|
Das D, Kumar A, Singh J, Pramanik S. Fluoroscopic “calcium sign” or reverse “c” sign of the aortic knuckle in a case of chronic total occlusion of left anterior descending coronary artery. Res Cardiovasc Med 2021;10:124-7
|How to cite this URL:|
Das D, Kumar A, Singh J, Pramanik S. Fluoroscopic “calcium sign” or reverse “c” sign of the aortic knuckle in a case of chronic total occlusion of left anterior descending coronary artery. Res Cardiovasc Med [serial online] 2021 [cited 2023 Mar 27];10:124-7. Available from: https://www.rcvmonline.com/text.asp?2021/10/4/124/337204
| Introduction|| |
Calcification of the aortic knuckle with dilatation of the aorta is a common phenomenon in the elderly population, otherwise known as the “unfolding of aorta”. Calcium sign in the aortic knuckle serves as an indirect radiographic evidence for the presence of aortic dissection. Aortic calcification along with the C sign has been reported in premature CAD (such as familial hypercholesterolemia) and vasculitis (such as Takayasu's arteritis). Interestingly we observed this reverse C shaped calcification of the aortic knuckle in a middle-aged person indirectly providing an evidence towards the presence of dense calcification of chronic total occlusion of left anterior descending coronary artery.
| Case Report|| |
A 42-year-old male nondiabetic, nonhypertensive, nonsmoker, and dyslipidemic presented to the cardiology outpatient department with a chief complaint of retrosternal squeezing type of chest discomfort for the past last 8 h associated with shortness of breath and diaphoresis. The pain was radiating to the jaw and left upper arm like a flower base with transient relief with sublingual nitroglycerine. At presentation, he had a blood pressure of 110/70 mmHg in the right arm supine position with a heart rate of 96 beats/min. Cardiovascular system examination revealed the presence of left ventricular fourth heart sound. Electrocardiogram revealed the presence of anterior wall ST-elevation myocardial infarction [Figure 1], and echocardiography revealed the presence of regional wall motion abnormality in the left anterior descending (LAD) coronary artery territory with mild left ventricular systolic dysfunction (EF-42%). High-sensitive troponin T was highly elevated (2600 ng/ml, cutoff 14 ng/ml). All the serum chemistries were within normal limit except the fasting lipid profile which was deranged with LDL value of 142 mg/dl and total cholesterol of 262 mg/dl. In view of ongoing angina within the window period of 12 h, he was taken for a right transradial coronary angiogram, which revealed the presence of chronic calcific total occlusion in mid-LAD coronary artery with significant occlusion in mid-RCA. In view of culprit vessel being the LAD coronary artery, we addressed the LAD coronary artery first, followed by the right coronary artery. LAD coronary artery was engaged with extra backup guide catheter 6 F (3.5), and the lesion was initially attempted to cross with Fielder FC wire and Fielder XT-A wire. Due to hard calcium in the proximal cap, the lesion could not be crossed with Fielder FC and the lesion was crossed with Gaia 3 wire with 1.5 mm × 8 mm balloon support. The lesion was predilated with 1.5 mm × 8 mm and 2.5 mm × 10 mm semi-compliant balloon at 12–16 atm pressure from distal to proximal segment followed by intracoronary nitroglycerine 200 μg. Then, a 0.014” balanced middleweight (BMW) wire was parked distally along the side of the Gaia 3 wire, and with this help of the “buddy wire technique,” a drug-eluting stent of 2.75 mm × 24 mm was deployed across the lesion at 14 atm pressure. Poststenting LAD revealed TIMI III flow and the patient's vitals were stable. Then, the RCA was engaged with Judkins right guide catheter and the lesion was crossed with the same BMW wire and directly stented with 2.75 mm × 40 mm drug-eluting stent at 14 atm pressure, poststenting RCA revealed TIMI III flow and vitals were stable. Post intervention, while removing the guide catheter, we noted the calcification of the aortic knuckle in an interesting reverse C shape. Momentarily, we thought it is guide catheter-induced aortic dissection producing calcium sign or C sign, but the patient did not complain of any tearing type of chest discomfort radiating to the back suggestive of aortic dissection and he was hemodynamically stable. Bedside echocardiography revealed aortic arch and knuckle calcification with dense chunk of calcium in the atherosclerotic plaque (marked with yellow arrow) [Figure 2] with normal diameter of aortic arch (17 mm) which is very rare to observe in fourth decade of life and established it as fluoroscopic “Calcium Sign” or Reverse “C” sign of aortic knuckle calcification [Figure 3] and [Figure 4]. Chest X-ray posteroanterior view also revealed the presence of reverse “C” sign or “Calcium Sign” [Figure 5]. Our case is a rare illustration of atherosclerotic calcification of the aorta in the middle age secondary to dyslipidemia with moderately elevated serum cholesterol. Our observation also suggests the fact that calcium sign or C sign is not limited to the aortic dissection only, it can also be seen in atherosclerotic aorta in the middle age and serves as an indirect marker for the presence of dense calcific atherosclerotic occlusion or chronic total occlusion (CTO) in the coronary arteries.
|Figure 1: Electrocardiogram showing anteroseptal Q wave ST-elevation myocardial infarction|
Click here to view
|Figure 2: Echocardiography showing hard chunk of calcium with atherosclerotic plaque in aortic knuckle. Black and Yellow arrows both indicate large chunk of calcium inside the atherosclerotic plaque|
Click here to view
|Figure 3: Fluoroscopic reverse C sign of aortic knuckle calcification with chronic total occlusion of mid left anterior descending coronary artery (AP cranial view)|
Click here to view
|Figure 4: Right anterior oblique cranial view showing reverse C sign of aortic knuckle calcification with chronic total occlusion of mid left anterior descending coronary artery|
Click here to view
| Discussion|| |
Aortic calcification occurs with advancement of age which is known as senile degenerative calcification of the aorta. Calcification of the aortic knuckle becomes evident in echocardiography with dilatation of the aorta known as “unfolding of the aorta” and it also fluoroscopically becomes evident during invasive coronary angiography. Dense calcification of the aorta serves as an indirect marker for the presence of severe calcific coronary artery disease (CAD). Calcification of the aortic knuckle becomes evident beyond sixth decade of life, but atherosclerotic calcification of the aortic knuckle in the fourth decade of life is very rare to encounter in routine clinical practice. “Calcium sign” or reverse C sign is defined as the separation of the intimal calcification from the outer aortic soft tissue border by more than 10 mm which is a specific sign for aortic dissection. It is found in 14% of descending aortic dissection and this finding is quite rare in aortic arch dissection. Majority of the aortic dissection finding in chest radiography are nonspecific. Previously, aortic calcification along with the C sign has been reported in premature CAD (such as familial hypercholesterolemia) and vasculitis (such as Takayasu's arteritis). We describe this radiographic finding in a case of CTO of LAD coronary artery in a middle-aged person with atherosclerotic aorta. This aortic knuckle calcium sign or reverse C sign is indirectly indicative of calcific obstruction in coronary artery. Chest X ray of the patient revealed no mediastinal widening suggestive of aortic dissection. Lin et al. described the presence of calcium sign in a rare case of aortic arch dissection in a 62-year-old male who could not be revived. That is why urgent echocardiographic evaluation should be done in a case with X-ray or fluoroscopic evidence of calcium sign. Urgent echocardiography was done in our case which revealed the presence of calcium chunk in the aortic knuckle with fluoroscopic evidence of calcium sign. Calcium sign is specific for aortic dissection, but it has low sensitivity. Lertsuwunseri et al. illustrated the calcium sign in a case of thoracic aortic dissection in Takayasu's arteritis. The patient was treated conservatively and they hypothesized that the healed aortopathy from chronic inflammation in Takayasu's arteritis is the cause behind aortic dissection in the above patient. When the calcium sign is tangential, it is otherwise known as “tangential calcium sign” indicative of aortic aneurysm rupture. The calcified intimal rim is discontinuous and is seen to tangentially point away from the aneurysm lumen. This sign is observed at the point of breach and is associated with retroperitoneal hemorrhage. Ciccone et al. described that the presence of calcium sign or C sign is a feature of acute aortic syndrome. Ponnatapura and Dyer. described the presence of aortic calcium sign in a case of long segment aortic dissection extending into the abdomen. Our case is the first fluoroscopic description of calcium sign in a middle-aged patient with calcific CTO of the LAD coronary artery, indicating the fact that presence of dense aortic calcification may be an indirect marker of severely calcific obstruction in one of the major coronaries. Intervention across atherosclerotic calcific aorta carries some special concerns: all the hard wires including guide wire, catheter, and balloon movement should be gentle across the calcific aorta as inadvertent handling carries high risk of calcium embolization causing periprocedural embolic cerebrovascular accident (CVA), reintroduction of the guide catheter should always be over an exchange wire, and removal of the catheters should be done carefully always noting the guide wire pointing beyond the guide catheter while removal. Transcatheter aortic valve replacement carries a high risk of periprocedural CVA in atherosclerotic calcific aorta due to risk of atherosclerotic debris or calcium embolization. The present case was calcification in the atherosclerotic aorta as renal profile including serum calcium and phosphorus was absolutely normal and serum parathyroid hormone was also absolutely normal. Due to the presence of hard calcium in the proximal cap of the CTO, the lesion could not be initially crossed with Fielder FC wire and the lesion was crossed after wire upgradation to Gaia 3 wire with active balloon support. Yielding a calcific lesion sometimes results in slow flow or no flow phenomenon, but the same was not observed in our case as we avoided aggressive predilatation of the lesion. We gently handled all the hardwires during percutaneous intervention and post procedure, the patient had no neurologic deficit. He was discharged uneventfully next day with aspirin 75 mg once daily, ticagrelor 90 mg twice daily, and atorvastatin 80 mg once daily with metoprolol 50 mg twice daily. Our case is unique and first to illustrate fluoroscopic calcium sign or C sign in the atherosclerotic aorta of a middle-aged male with densely calcific CTO of mid-LAD coronary artery, indicating the fact that calcium sign or reverse 3 sign may be an indirect marker of severely calcific atherosclerotic obstructive CAD in one of the major coronary arteries.
| Conclusion|| |
Our case is the first and unique illustration of presence of fluoroscopic Calcium or C sign in a middle-aged person with atherosclerotic aortic arch with densely calcific CTO of mid LAD coronary artery with J - CTO score of 3. Presence of calcium sign or reverse 3 sign can be an indirect marker of severely calcific obstructive atherosclerotic CAD in one of the major coronaries.
Institutional Ethical Committee (IEC) clearance has been obtained.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Klompas M. Does this patient have an acute thoracic aortic dissection? JAMA 2002;287:2262-72.
Slater EE, DeSanctis RW. The clinical recognition of dissecting aortic aneurysm. Am J Med 1976;60:625-33.
von Kodolitsch Y, Schwartz AG, Nienaber CA. Clinical prediction of acute aortic dissection. Arch Intern Med 2000;160:2977-82.
Lin SH, Huang SH, Liao WH. The calcium sign of aortic arch dissection. BMJ Case Rep 2013;2013:bcr2013200658.
Wang YC, Hwang JJ, Lai LP, Tseng CD. Iatrogenic aortic dissection during left subclavian artery stenting: Immediate detection by calcium sign under fluoroscope. Cardiovasc Intervent Radiol 2011;34 Suppl 2:S36-9.
Lertsuwunseri V, Chattranukulchai P, Tumkosit M, Boonyaratavej S. Calcium sign of thoracic aortic dissection in Takayasu's arteritis. BMJ Case Rep 2018;2018:r-224313.
Ciccone MM, Dentamaro I, Masi F, Carbonara S, Ricci G. Advances in the diagnosis of acute aortic syndromes: Role of imaging techniques. Vasc Med 2016;21:239-50.
Ponnatapura J, Dyer RB. The “tangential calcium” sign. Abdom Radiol (NY) 2019;44:2933-4.
Watchmaker LE, Watchmaker JM, Watchmaker GP. Arterial calcification on wrist radiographs may suggest need for evaluation of atherosclerosis in asymptomatic individuals. Case Rep Radiol 2019;2019:6156948.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]