Download Contrast Pooling and Layering in a Patient with Left Main Coronary

Acta Cardiol Sin 2015;31:461-463
Case Report
doi: 10.6515/ACS20150511A
Contrast Pooling and Layering in a Patient with
Left Main Coronary Artery Occlusion and
Cardiogenic Shock
Tzu-Chiao Lin,1 Chin-Sheng Lin,1 Hsian-He Hsu2 and Jun-Ting Liou1
A 57-year-old male with type 2 diabetes mellitus presented to the emergency department with sudden onset of
chest pain. Shock status and considerably low right arm blood pressure were detected. The patient underwent
contrast-enhanced computed tomography (CT) which revealed dependent contrast pooling and layering of
contrast material within the inferior vena cava. Post-processing CT angiography depicted total occlusion of the left
main coronary artery. Sudden cardiac arrest developed after CT examination, and following emergency coronary
angiography we confirmed the diagnosis of left main coronary artery occlusion and cardiogenic shock. Clinical
physicians should recognize these CT findings of imminent cardiovascular decompensation and provide prompt
medical management to prevent further patient deterioration.
Key Words:
Cardiogenic shock · Dependent pooling · Layering · Left main coronary artery disease
INTRODUCTION
partment with sudden onset of squeezing chest pain
and cold sweating. Relevant past history was unremarkable except for type 2 diabetes mellitus under treatment
with oral anti-diabetic agents for more than 3 years. His
blood pressure was 86/54 mmHg, heart rate 64 beats per
minute, respiratory rate 24 breaths per minute, and
SaO2 of 93% when using ambient air. Physical examination revealed a regular heart beat without audible murmur, and crackle breathing sounds at bilateral basal lung
fields. In addition, the patient had lower right arm BP
(59/23 mmHg) as compared to his other limbs. A 12-lead
electrocardiogram showed normal sinus rhythm with ST
segment elevation at lead aVR, and ST segment depression at leads II, III, and aVF (Figure 1A). Transthoracic
echocardiogram demonstrated severe generalized hypokinesia of the left ventricle with ejection fraction about
20% and mild aortic regurgitation.
Due to only limited time for adequate diagnosis and
further management, contrast-enhanced CT was first
considered for the emergency. This imaging excluded
aortic dissection but revealed dependent contrast pooling and layering of contrast material and blood within
the inferior vena cava (Figure 1B, 1C). Moreover, post-
Computed tomography (CT) is an important and
popular diagnostic tool. Cardiogenic shock is defined as
decreased cardiac output leading to circulatory failure
and tissue hypoperfusion. We present a rare case of
documented left main coronary artery total occlusion
with characteristic CT features of imminent cardiogenic
shock.
CASE REPORT
A 57-year-old man presented to the emergency de-
Received: May 2, 2014
Accepted: May 11, 2015
1
Division of Cardiology, Department of Medicine; 2Department of
Radiology, Tri-Service General Hospital, National Defense Medical
Center, Taipei, Taiwan.
Address correspondence and reprint requests to: Dr. Jun-Ting Liou,
Division of Cardiology, Department of Medicine, Tri-Service General
Hospital, No. 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei,
Taiwan. Tel: 886-2-8792-7160; Fax: 886-2-6601-2656; E-mail: ljtmail
@gmail.com
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Acta Cardiol Sin 2015;31:461-463
Tzu-Chiao Lin et al.
A
B
C
D
Figure 1. (A) A 12-lead electrocardiogram revealing ST segment elevation in lead aVR and ST segment depression in lead II, III, and aVF. (B)
Contrast-enhanced Computed tomography (CT) demonstrating dependent venous pooling of contrast material in dependent hepatic veins (arrow)
and inferior vena cava (IVC). (C) Venous pooling and layering of contrast material within superior vena cava, right atrium of heart, inferior vena cava
(arrow), and other dependent venous structures (arrow head). (D) CT angiogram illustrating total occlusion of left main coronary artery (LMCA)
(arrow).
processing CT angiography depicted total occlusion of
the left main coronary artery (LMCA) (Figure 1D). Sudden cardiac arrest occurred subsequent to the patient’s
CT examination. Aggressive resuscitation efforts were
applied, along with intra-aortic balloon pump counterpulsation, emergent cardiac catheterization and digital
subtraction coronary angiography. This intervention and
its associated procedures confirmed the diagnosis of
LMCA total occlusion (Figure 2A, 2B). However, the
patient expired despite temporary revascularization of
LMCA by balloon dilatation.
A
B
Figure 2. (A) Digital subtraction coronary angiogram revealing total
occlusion over LMCA (arrow). (B) After emergent percutaneous coronary
intervention, TIMI 1 flow over left anterior descending coronary artery
and left circumflex coronary artery were noted. Abbreviations are in
Figure 1.
DISCUSSION
shock status should receive surgery immediately. In the
current report, we presented a case of LMCA disease
with cardiogenic shock who was initially misdiagnosed
as AAS. Moreover, we demonstrated the rare CT images
of dependent venous contrast pooling as signs of documented total occlusion of LMCA, cardiogenic shock and
markedly depressed cardiac output.
In patients with acute chest pain and shock status, it
is important and usually a diagnostic challenge to differentiate acute coronary syndrome (ACS) from acute aortic syndrome (AAS), since the treatment strategies for
these two disease are completely different. In contrast
to patients with ACS, who typically require primary percutaneous coronary intervention, patients with AAS and
Acta Cardiol Sin 2015;31:461-463
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CT Manifestation of Cardiogenic Shock
images.2-4 Thus, dependent venous pooling implies cardiac pump dysfunction which involves a failure to propel
blood against gravity.
In conclusion, we demonstrated the rare CT features
of a case of LMCA disease with cardiogenic shock. The
contrast-enhanced CT findings of dependent venous
contrast pooling and contrast-blood layering suggest
signs of cardiogenic shock and carry a very poor prognosis for the patient. Clinicians should be notified immediately and provide prompt medical management to avoid
a catastrophic outcome.
There have been a scant few reports regarding the
CT features of cardiogenic shock.1-4 The underlying lethal disease of these patients includes aortic dissection,
trauma with massive bleeding, intra-abdominal infection with septic shock, and acute myocardial infarction
with cardiogenic shock.1-4 Typical CT features in these
shock patients demonstrated contrast collecting in the
dependent portion of the superior vena cava and the inferior vena cava (IVC), forming a blood-contrast level.1
Moreover, the retrograde contrast from IVC to the right
hepatic vein, which then densely opacified the right
lobe liver parenchyma.1
With normal physiological flow, specific gravity has
little effect on the contrast agent dynamics. However, in
patients with cardiogenic shock, both arterial and venous blood flows dramatically decrease, and even stop.
Contrast agents are heavier than blood and tend to accumulate in the dependent parts of the venous system.
Under such circumstances, the distribution of the contrast agent depends largely on its density and specific
gravity, as well as the injected volume and duration.1
Therefore, most of the injected contrast agents in these
patients are found in the superior vena cava, the inferior
vena cava, and the dependent parts of the body, including the organs and vessels, causing venous pooling and
layering of contrast material in contrast-enhanced CT
REFERENCES
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2. Roth C, Sneider M, Bogot N, et al. Dependent venous contrast
pooling and layering: a sign of imminent cardiogenic shock. AJR
Am J Roentgenol 2006;186:1116-9.
3. Jana M, Gamanagatti SR, Kumar A. Case series: CT scan in cardiac
arrest and imminent cardiogenic shock. Indian J Radiol Imaging
2010;20:150-3.
4. Bagheri SM, Taheri MS, Pourghorban R, Shabani M. Computed
tomographic imaging features of sudden cardiac arrest and impending cardiogenic shock. J Comput Assist Tomogr 2012;36:
291-4.
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Acta Cardiol Sin 2015;31:461-463