1. Garry Choy, MD1; Brian Ghoshhajra, MD, MBA1; Terrance T. Healey, MD2; Carlos A. Rojas, MD1; Efren Flores, MD1; Axel Scherer, MD3; Sung Han Kim, MD4; Suhny Abbara, MD1
Coronary Aneurysms: What Every Radiologist Needs to Know
1Department of Radiology, MASSACHUSETTS GENERAL HOSPITAL • 1,4HARVARD MEDICAL SCHOOL • 4Mt. Auburn Hospital • 2Department of Radiology, Rhode Island Hospital, Brown Medical School • 3 Institute of Diagnostic Radiology, Heinrich-Heine University
References
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strategies. Ann Thorac Surg. 2007; 84: e10–e11.
5. Harandi S, Johnston SB, Wood RE, et al. Operative therapy of coronary arterial aneurysm. Am J Cardiol. 1999; 83:1290–1293.
6. Hartnell GG, Parnell BM, Pridie RB. Coronary artery ectasia: its prevalence and clinical significance in 4993 patients. Br Heart J. 1985;
54:392–395.
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8. Takaki MT, Dubinsky TJ, Warren BH, Mitsumori L, Shuman WP. Nonatherosclerotic cardiovascular findings on MDCT coronary
angiography: a selection of abnormalities. AJR Am J Roentgenol 2008;190:934-46.
9. Satran A, Bart BA, Henry CR, Murad MB, Talukdar S, Satran D, Henry TD. Increased prevalence of coronary artery aneurysms among
cocaine users. Circulation. 2005 May 17;111(19):2424-9. Epub 2005 May 9.
10. ECG-gated Cardiac CT Evaluation of a Saphenous Vein Graft Aneurysm Pre- and Post- Percutaneous
Intervention, Rojas CA, MD, El-Sherief A., MD, Choy G., MD, Medina-Zulaga H., MD, Inglessis I., MD,
Abbara S., MD and Mamuya W., MD, Cardiovascular Images, Massachusetts General Hospital, 2009
http://www.mgh-cardiovascimages.org/
PURPOSE
To review the variety and range of coronary artery
and bypass graft aneurysms
To discuss the findings and diagnostic criteria
To explain the pathological processes
What is a coronary artery
aneurysm?
Definition
Coronaryarterydiameter>1.5Xnormaladjacentsegdiameter
Types
• Focal or diffuse
• Fusiform or saccular
Clinical Implications
• Often asymptomatic but patients can present with
angina, myocardial infarction, or sudden death
• Otheradverseeventsincludethrombosis,thromboembolism,
AV fistulae, vasospasm, and rupture
• Incidental finding on coronary angiograms
Pathophysiology
Thought to be similar to that for aneurysms of
larger vessels, with destruction of the vessel
media resulting in increased wall stress and
subsequent dilation
Epidemiology
• Atherosclerosis most common cause in USA
• Kawasaki Disease most common cause globally
• Based on several angiographic studies,
incidence of coronary artery aneurysms ranges
from 0.3% to 5.3% of the population
• Incidence has been reported in up to 1.8% in an
angiographic study [ref: Nichols]
• Right coronary artery is most commonly affected
(40–87% of aneurysms), followed by left circumflex
or left anterior descending artery, depending on
the study [ref: Villines]
• Three-vessel or left main involvement is rare
Best imaging tool
• Coronary CTA or Coronary angiography
• Goal is to establish diagnosis and to provide additional
information about size, shape, location, and number of
existing anomalies
• Imagingiscriticalinfollow-uptoensurestabilityofaneurysms
Treatments
• Anticoagulants, antiplatelet therapy, bypass, covered stents
• Treatment options consist of surgical, percutaneous,
and medical approaches
• At mean of 3.2 years follow-up, mortality rates after
surgery and medical management were 7.7% and 13%
where follow-up was available), respectively
•Similarmortalityratesat5yrswerereportedinEuropean
CoronarySurgeryStudyofpatientstreatedsurgically
ormedically
• Operative therapy includes CABG, aneurysm ligation,
resection, or marsupialization with interposition graft
• Percutaneous treatment is a newer option and includes
stenting and coiling
Morphology of Coronary
Artery Aneurysms
Fusiform or saccular dilatation
Can be associated with thrombosis
Atherosclerotic Disease
Findings
Fig 1A - B: Atherosclerotic aneurysmal dilatation of the distal
left main to 9 mm, with continuation of aneurysm into the
proximal LAD
Fig 2A - B: Massive atherosclerotic left main to LAD coronary
aneurysm in a different patient
Fig 3A, B, C: Saccular aneurysm in setting of Atherosclerotic
Disease in proximal LAD
Teaching Points - Atherosclerotic Disease
Most common cause in USA
Male-predominant
Pathophysiology
Atherosclerotic related inflammation-mediated
thinning or destruction of media; increased MMP (matrix
metalloproteinase) activity resulting in proteolysis of
extracellular matrix proteins have been implicated in
atherosclerosis
Symptoms and complications related to concurrent degree
of CAD or obstructive coronary disease
Teaching Points – Cocaine
Cocaine mediated aneurysms have a similar appearance as
aneurysms related to atherosclerotic disease
Coronary aneurysms and occur between 0.2% to 5.3% of
patients referred for angiography
T. Henry, et al found that among cocaine users, up to 30% in a
study of 112 patients had coronary artery aneurysms
Average age was 44 years old and predominantly male
Potential pathophysiological mechanism may be tied to
chemically-mediated severe local episodic hypertension
and vasoconstriction with direct endothelial damage
predisposing to aneurysm formation
Saccular or fusiform morphology of aneurysms not unlike in
appearance with aneurysms found in atherosclerotic disease
Etiologies
of Coronary Aneurysms
Atherosclerotic Disease
(Most common cause in USA)
Kawasaki Disease
(Most common cause worldwide)
Connective Tissue Disease
(SLE, Marfan, Behcet’s Disease)
Pseudoaneurysms
Saphenous Vein Graft Aneurysm
Post-Traumatic Pseudoaneurysm
Infection
Coronary Fistulas
Cocaine Use
Connective Tissue Disease - Marfan Syndrome
Findings
Fig 16A, B, C, D: Patient with both sinus of Valsalva aneurysm and fusiform aneurysm involving distal left main, proximal
LAD, proximal LCX in setting of Marfan Syndrome. Only minimal atherosclerotic disease with tiny focus calcification
seen in distal left main
Teaching Points – Connective Tissue Disease
Pathophysiology
Linked to excess TGF-beta production (protein that is homologous with family of proteins in microfibrils in elastin fibers)
Examples of connective tissue diseases associated with coronary aneurysms:
Marfan Syndrome: Mutation in gene encoding fibrillin; cystic medial degeneration common feature of aneurysms
Behcet’s: Form of vasculitis associated with systemic vascular inflammation; patients also present with oral ulcers,
genital ulcers, skill lesions, uveitis
Kawasaki Disease
Findings
Fig 4A, B, C, D: Fusiform dilatation of the proximal RCA in patient with minimal atherosclerosis and
history of Kawasaki Disease
Fig 5A, B, C: Multiple fusiform aneurysms in proximal RCA and LAD. Calcification possibly related to
chronic nature of thrombosis in setting of Kawasaki Disease
Fig 6: Partially thrombosed RCA aneurysm in patient with Kawasaki Disease
Fig 7A - B: Multiple partially calcified fusiform aneurysms in LAD and diagonal branch in patient with
Kawasaki Disease.
Teaching Points – Kawasaki Disease
Kawasaki Disease - mucocutaneous lymph node syndrome; self limited systemic vasculitis of
childhood affecting multiple systems including coronary arteries
Epidemiology
Mainly Asian population, 50/100,000 children in Japan (10X higher incidence than US)
Pathophysiology
Generalized systemic vasculitis involving large, medium sized arteries associated with aneurysm
and thrombosis
Cardiac findings in Kawasaki Disease include myocarditis, coronary aneurysms, or arrhythmias
Kawasaki Disease patients at risk for thrombosis due to increased platelets (thrombosis often found in
aneurysms); aneurysms may not be discovered until adulthood
Treatment
Antiplatelet or anticoagulation therapy
Post-Traumatic Pseudoaneurysm
Findings
Fig 8: This patient underwent balloon angioplasty and stenting of the left main to LAD and circumflex after
acute occlusion. Follow-up catheterization 2 weeks later for recurrent chest pain demonstrates a post-
traumatic pseudoaneurysm at the angioplasty and stent site. Follow-up CTA 3 months later demonstrates
near-complete resolution
Fig 9: Pseudoaneurysm of the left main in a different patient after balloon angioplasty
Fig 10: Catheter angiogram demonstrates an aneurysmal saphenous vein graft
Fig 11: Unenhanced axial CT demonstrates mural thrombus in the aneurysm
Fig 12A, B, C, D: Enhanced CTA demonstrates the lumen and the true diameter of the aneurysm
Note the dilated apical aneurysm and calcified papillary muscle, confirming a remote MI
Figure 13A: Pre-intervention axial multiplanar reformation (MPR) image demonstrating a large SVG aneurysm
with associated thrombus within the aneurysm
Figure 13B: Pre-intervention coronal maximum intensity projection (MIP) image demonstrating a large
SVG-PLV aneurysm
Figure 13C: Post-intervention axial MPR image demonstrating successful stenting and exclusion of the
SVG-PLV aneurysm
Figure 13D: Post-intervention coronal MIP image demonstrating successful exclusion of the SVG-PLV aneurysm,
without evidence of an endoleak
Fig 14A, B, C: Extremely large Saphenous Vein Graft Pseudoaneurysm with associated median
sternotomy dehiscence
Fig 15A, B, C: Mycotic Pseudoaneurysm – Infection/Traumatic
Images demonstrate a patient with inflammatory pericarditis from group B streptococcus infection. 6 weeks
prior, pericardiocentesis revealed Group-C-Streptococci. No history of childhood illness nor connective tissue disease.
CTA shows focal saccular aneurysm of the RCA. Rim-enhancing pericardial fluid collection along the left
lateral border of the heart
Fig 15D: Double-Oblique Coronal. Arterial-phase gated CTA demonstrates a 2-3 cm collection of contrast in
continuity with the distal RCA. Narrow connection to parent vessel
Fig 15E: Catheter Coronary Angiography. Coronary angiography demonstrates collection of contrast in distal
RCA confirming CTA finding
Fig 15F: Post-Stent CTA (with residual contrast in excluded sac). Because of the tenuous condition of the
patient, a covered stent was placed in the RCA. In order to secure a landing zone, the PDA was sacrificed.
The patient suffered a small inferior wall MI
Teaching Points - Pseudoaneurysm
Most commonly, pseudoaneurysms are post-traumatic in nature related to intervention or surgery such as
CABG, cardiac angiography in setting of stent placement or angioplasty or pericardiocentesis
Infection may also result in pseudoaneurysm
Fig 01A Fig 01B
Fig 02A Fig 02B
Fig 03A Fig 03B
Fig 03C
Fig 04A Fig 04B
Fig 04C Fig 04D
Fig 05A
Coronary Fistulas
Findings
Fig 17A - B: Anterior and inferior-posterior volume rendered
images demonstrate an enlarged, tortuous RCA, with the
PLV branch connecting to the coronary sinus (arrow). Flow
therefore shunts from the high-pressure coronary artery to
the low-pressure coronary sinus
Fig 18A - B: Coronary fistula of left circumflex artery (LCX) to
the coronary sinus. The LCX (red arrow) is diffusely ectatic
with a large focal aneurysm (yellow arrow) immediately
proximal to anastamosis with coronary sinus (orange arrow)
Teaching Points – Coronary Fistulas
Consider coronary fistula as a differential consideration
when aneurysmal dilatation of coronary artery is seen
Abnormal direct connection between coronary artery and a
cardiac chamber
Etiology
Usually congenital in nature
Latrogenic after biopsy or intervention
Trauma
Connects high pressure system to low pressure system
Best imaging findings
Tortuous and enhancing epicardial arteries
Markedly enlarged and tortuous coronary arteries;
aneurysmal dilatation immediately proximal to drainage site
Fig 05B
Fig 05C
Fig 06
Fig 07A
Fig 07B
Fig 08 Fig 09
Fig 10 Fig 11
Fig 12A Fig 12B Fig 12C Fig 12D
Fig 14A Fig 14B Fig 14C
Fig 15A Fig 15B Fig 15C Fig 15D Fig 15E Fig 15F
Fig 16A Fig 16B
Fig 16C Fig 16D
Fig 17A Fig 17B Fig 18A Fig 18B
Fig 13A Fig 13B Fig 13C Fig 13D