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DR. MOHAMED MUSTAFAINTERNAL MEDICINE
KHUH
Coronary Ectasia
What is Coronary Artery Ectasia (CAE)?
Relatively common entity inappropriate dilatation of the coronary
vasculatureEtiology unknown
Multifactorial: genetic predisposition risk factors for coronary artery disease abnormal vessel wall metabolism.
Definition
CAE: dilatation of an arterial segment to a diameter of 1.5 times that of the adjacent normal coronary artery.(1)
(1) Hartnell GG, Parnell BM, Pridie RB. Coronary artery ectasia, its prevalence and clinical significance in 4993 patients. Br Heart J 1985: 54: 392-5
Etiology-Prevalence
CAE can be found in 3-8% of angiographic and in 0.22% to 1.4% of autopsy series
It can be either be diffuse, affecting the entire length of a coronary artery, or localized
Causes: Atherosclerosis 50% Congenital 20-30% Inflammatory/connective Tissue diseases 10-20%: scleroderma, Ehlers–Danlos syndrome, different types of ANCA- related vasculitis,
syphilitic aortitis and Kawasaki disease .
NB Acquired CAE should be differentiated from coronary aneurysms following coronary interventions. Occasionally, large ulcerated coronary plaques can be misinterpreted angiographically as coronary aneurysms.
Pathophysiology
Aneurismal segments produce sluggish or turbulent blood flow leading to typical exercise-induced angina pectoris and myocardial infarction (regardless of the severity of coexisting stenotic lesions)
All three coronary vessels can be affected by CAE almost 75% of patients will have an isolated artery that is
ectatic. In concomitant CAD, the proximal and mid
segment of the right coronary artery is the mostly affected.
This process of “arterial remodeling” is fundamental to the pathophysiology of CAD. The in vivo experience with IVUS has confirmed that both arterial expansion and shrinkage can be a manifestation of coronary atherosclerosis.
Positive remodelling (arterial expansion) is frequently associated with unstable coronary syndromes
Negative remodelling (arterial shrinkage) is associated with stable coronary syndromes.
Classification
By SeverityType I : Diffuse ectasia of 1 vessel & localized
ecatsia in another vesselType II: Diffuse ectasia of 1 vessel onlyType III: localized or segmental ectasia
By Anatomical shape:Fusiform or saccular ectatic segment
Classification of coronary artery ectasia, as shown with volume-rendered images of the coronary tree.
Díaz-Zamudio M et al. Radiographics 2009;29:1939-1954
©2009 by Radiological Society of North America
Classification of coronary artery ectasia, as shown with volume-rendered images of the coronary tree.
Díaz-Zamudio M et al. Radiographics 2009;29:1939-1954
©2009 by Radiological Society of North America
Classification of coronary artery ectasia, as shown with volume-rendered images of the coronary tree.
Díaz-Zamudio M et al. Radiographics 2009;29:1939-1954
©2009 by Radiological Society of North America
Diagnostic Approach
X-Ray Coronary Angiography
CT Coronary Angiography
Magnetic Resonance Angiography
Xray Coronary AngiogrpahyX-ray coronary angiography is the main
diagnostic technique IVUS is an excellent tool to assess luminal
size and characterize arterial wall changes. Angiographic signs of turbulent and stagnant
flow include delayed antegrade dye filling, a segmental back flow phenomenon and local deposition of dye in the dilated coronary segment.
Magnetic Resonance Angiography (MRA) The correct follow-up of ectatic vessels is hampered by the need for
repeated angiograms. 3D, non-contrast enhanced, free-breathing coronary magnetic
resonance angiography facilitates visualization of the vast majority of the proximal and middle segments of the coronary arteries.
MRA has already been of clinical value for the assessment of anomalous CAD, and it is in some cases superior to x-ray coronary angiography in delineating the course of anomalous vessel.
However it is proposed as a valuable tool for patients who present with severe left ventricular systolic dysfunction, where the underlying disease is either severe multi-vessel coronary artery disease or nonischemic cardiomyopathy.
MRA is equal to QCA in terms of diagostic value, however, Compared with computed tomography, magnetic resonance
angiography has the advantage of requiring no exposure to radiation or injection of a contrast agent.
CT Coronary AngiographyRecently, CT coronary angiography has been used in the
evaluation of ectatic vessels. Coronary artery ectasia usually was associated with
atheromatous changes, but not with significant CAD and thrombosis was a rare complication.
Contrast attenuation measurements with CTCA correlated well with the flow alterations assessed with classic X-ray coronary angiography.
However, CACT cannot be suggested as a technique of choice for patients’ follow-up due to high radiation doses.
Further improvements in terms of radiation doses are expected with interest in the near future.
Treatment
Previous studies based on the significant flow disturbances within the ectatic segments, suggested chronic anticoagulation as main therapy. However, this treatment has not been prospectively tested.
The coexistence of CAE with obstructive coronary lesions in the great majority of patients and the observed incidence of myocardial infarction - even in patients with isolated coronary ectasias - suggested the generalized administration of ASPIRIN in all patients with CAE.
Vaso Dilators Nitrates can cause further coronary
epicardial dilation and have been shown to exacerbate myocardial ischemia and are discouraged in patients with isolated CAE.
Surgical TreatmentFor patients with coexisting obstructive
lesions and symptoms or signs of significant ischemia despite medical therapy, percutaneous and/or surgical coronary vascularisation can safely and effectively restore normal myocardial perfusion.
Coronary artery bypass grafting has been used for the treatment of significant CAD co-existing with ectatic coronary segments
Heart transplant