Learning objectives
The purpose of this poster is to demonstrate the computed tomography (CT) protocol and findings of aortocaval fistula (ACF).
Background
Abominal aortic aneurysms (AAA) most commonly rupture into the retroperitoneal space or peritoneal cavity [1]. ACF presents a rare complication of AAA [1,2]. It occurs in less than 1% of all aneurisms and between 3-7% of all ruptured AAAs. ACF occurs after an AAA erodes the wall of the inferior vena cava (IVC) [2,3]. Pathophysiologicaly, aortocaval fistula is the result of periaortic inflammation, adherence of adjacent vessels and pressure necrosis of the vessel wall [3]. It can be spontaneus or caused by: trauma, syphilis, myotic...
Findings and procedure details
The scanning protocol for AAS should include native CT scans of the chest and abdomen, and a contrast-enhanced CT of the aorta in arterial phase with ECG gating of the thoracic area, followed by venous phase [12]. The aim of using ECG gating is to elimination motion artefacts of the heart. This helps us with exclusion of other causes of chest pain (acute aortic syndrome, acute coronary myocardial infarction). ECG gating should be performed whenever the aortic root and coronary arteries needs to be evaluated...
Conclusion
ACF is according to literature accurately periopertively diagnosed in only up to 50%, leading to an increase of mortality from 20% to 55%. Therefore, optimal imaging protocol for detecion of ACF and its complications, is mandatory.
Personal information and conflict of interest
N. Hanžič; Maribor/SI - nothing to disclose M. Pirnat; Maribor/SI - nothing to disclose
References
1. Singh N, Kuriakose AM, George RA, Vaidya. Computed tomographic diagnosis of aortocaval fistula. S Afr J Rad. 2018; 22(1): a1363.
2. Aortocaval fistula. Available at https://radiopaedia.org/articles/aortocaval-fistula-2. Accessed January 3, 2020.
3. Potyk DK, Guthrie CR. Spontaneous aortocaval fistula. Ann Emerg Med. 1995; 25(3):424-427.
4. De Rango P, Parlani G, Cieri E, Verzini F, Isernia G, Silvestri V, Cao P. Paradoxical pulmonary embolism with spontaneous aortocaval fistula. Ann Vasc Surg. 2012; 26(5):739-746.
5. Clinical features and diagnosis of abdominal aortic aneurysm. Available at https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-abdominal-aortic-aneurysm. Accessed...