Clinical History
A 61-year-old man with history of smoking, with family history of ischaemic heart disease underwent a CT coronary angiography examination. He referred dyspnoea on exertion with anterior chest pain and ventricular extrasystoles on ECG stress test.
Imaging Findings
CT angiography showed ectasia (fig.1-2) of the distal segment of the left main coronary artery and the proximal segment of the left descending artery, where there was a mixed plaque that determined luminal stenosis less than 50% (fig.1a-b). Segmental dilatations were also present in the distal segment of the circumflex artery and in the posterior descending artery (fig.1c-d). The right coronary artery was ectatic at its middle segment with a 1.5-cm-large aneurysm in its distal segment (fig.1e-f). A mixed plaque was also found at the origin of the first obtuse marginal branch, resulting in lumen stenosis around 50% (fig.1g).
Discussion
Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of a coronary artery. The term ectasia is reserved to mean a diffuse dilatation (>1.5 times the normal vessel diameter) of the coronary arteries involving 50% or more of the length of the artery [1].
Not all patients with ectasia are symptomatic and undergo coronary angiography (either conventional or CT), so the real incidence is unknown. The reported frequency varies between 1.5 and 5%, with an occurrence rate of 10% among Indians and with male predominance. In the largest series from the Coronary Artery Surgery Study (CASS) registry, authors found CAE in 4.9% of more than 20,000 coronary angiograms they reviewed.
Diffuse ectasia of two or three vessels is classified as Type I, diffuse disease in one vessel and localized disease in another vessel as Type II, diffuse ectasia of one vessel only as Type III, and localized or segmental ectasia as Type IV. All three coronary vessels can be affected by CAE, but in 75% of patients an isolated artery is ectatic. In patients with concomitant coronary artery disease, the proximal and mid segments of the right coronary artery are the most frequently involved, followed by the left anterior descending artery and the circumflex artery [2].
More than half of cases of CAE are due to coronary atherosclerosis, but occasionally, they are related to other pathological entities. CAE has been observed in association with connective tissue disorders such as scleroderma, Ehlers–Danlos syndrome and polyarteritis nodosa, but also with bacterial infections and Kawasaki disease. In a small percentage of patients, CAE can be congenital in origin. The specific cause of CAE are essentially unknown, but the hypotheses for the origin of CAE revolve around the vascular endothelium and the biological properties of the arterial wall.
The clinical manifestations depend on the underlying cause; in those cases associated with atherosclerosis, the manifestations are similar to those seen in coronary artery disease, such as stable angina and acute coronary syndromes.
Coronary angiography remains the gold standard for the assessment of CAE. IVUS is an excellent tool to assess luminal size and characterize arterial wall changes. Coronary CT angiography provides a safe noninvasive approach for accurately showing the lumen and wall of the coronary arteries.
Conservative measures consist of medical treatment with anticoagulant and antiplatelet drugs to avoid thromboembolic events. Surgery can be considered to avoid complications [3].
Differential Diagnosis List
Atherosclerotic ectasia of coronary arteries
Coronary pseudoaneurysm
Coronary aneurysm
Dilated coronary fistula
Kawasaki disease
Final Diagnosis
Atherosclerotic ectasia of coronary arteries
