Dilated Accessory Hemiazygos Vein Mimicking Aortic Dissection in Setting of Absent Left Brachiocephalic Vein

Krunal H Patel¹, Vaibhavi Uppin², Harshith Chandrakumar¹, Yuvraj Singh Chowdhury², Jonathan Ramalho², Basil Elamir¹, Loius Sacicciioli², Harjinder Gill¹, Sarah Hennis¹ and Samy I. McFarlane^1,

¹Department of Internal Medicine, State University of New York, Downstate Health Science University, Brooklyn, NY, USA - 11203

²Division of Cardiovascular Disease, State University of New York, Downstate Health Science University, Brooklyn, NY, USA - 11203

Cite this paper

Krunal H Patel, Vaibhavi Uppin, Harshith Chandrakumar, Yuvraj Singh Chowdhury, Jonathan Ramalho, Basil Elamir, Loius Sacicciioli, Harjinder Gill, Sarah Hennis and Samy I. McFarlane. Dilated Accessory Hemiazygos Vein Mimicking Aortic Dissection in Setting of Absent Left Brachiocephalic Vein. American Journal of Medical Case Reports. 2021; 9(2):125-130. doi: 10.12691/AJMCR-9-2-7

Abstract

Although uncommon, aortic dissection can be rapidly fatal with a 20% out-of-hospital mortality which increases at a rate of 1 to 3% every hour [1]. An expeditious diagnosis of acute aortic dissection is therefore imperative. One of the most advantageous diagnostic modalities utilized in the setting of acute aortic dissection is a transesophageal echocardiogram (TEE). In an acute setting, TEE is preferred because of its ability to provide a timely and definitive diagnosis [2]. Despite its diagnostic convenience, clinicians must be aware that there are several entities that may mimic aortic dissection. One of these entities includes a dilated accessory hemiazygos vein. In this report, we present a case of a 66-year-old woman who was found to have a possible Stanford type B dissection in the descending thoracic aorta on a TEE exam in the context of work up prior to an elective electrophysiology study and ablation for paroxysmal atrial fibrillation. CT angiography, however, revealed a dilated accessory hemiazygos vein, a rare congenital vascular anomaly that could potentially mimic aortic dissection leading to misdiagnosis and potentially unnecessary interventions.

Keywords

aortic dissection, transesophageal echocardiogram, hemiazygos vein, brachiocephalic vein, congenital vascular anomaly

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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