Incidentally detected aorto-right atrial fistula in asymptomatic patient with operated aortic dissection

Congenital Aorto-Cardiac Connections (CACC) Revisited: Introduction of a Novel Anatomic-therapeutic Classification

Abnormal congenital aorto-cardiac communications (CACC) are a heterogeneous constellation of anomalies that provide an abnormal connection between the aorta and other cardiac chambers or structures, including the atria, ventricles, the main pulmonary artery, and the coronary sinus. The current terminology of CACC has significant errors and shortcomings including inconsistent and interchangeable use of terms of fistula and tunnel and lack of an inclusive classification with practical information on therapeutic management. The aims of this study were threefold: firstly, to perform a concise narrative review of congenital pathologic connections between the aortic root and cardiac chambers which include rupture of congenital sinus of Valsalva aneurysm, aorto-left ventricular and less commonly right ventricular tunnels, coronary cameral fistulas, and aorto-atrial communications; secondly, to investigate the differentiating features of the so-called aorta right atrial tunnel (ARAT), with and without coronary artery take-off from the tunnel, and coronary cameral fistula (CCF) by applying a differential diagnostic assistance toolbox to two groups of patients with ARAT and CCF; and lastly, to propose a practical and inclusive anatomic-therapeutic classification for CACCs. The two main cornerstones of the proposed classification are the type of the connector between the aorta and cardiac chamber (hole versus passage) and the nature of the connecting passage ( anatomic versus extra-anatomic). We classified CACCs into three types. Depending on the intramural versus extramural course of the extra-anatomic connecting passage, type 3 is further subdivided into type 3A and type 3B.

Aortic Fistulas: Pathophysiologic Features, Imaging Findings, and Diagnostic Pitfalls

Fistulas between the aorta and surrounding organs are extremely rare but can be fatal if they are not identified and treated promptly. Most of these fistulas are associated with a history of trauma or vascular intervention. However, spontaneous aortic fistulas (AoFs) can develop in patients with weakened vasculature, which can be due to advanced atherosclerotic disease, collagen-vascular disease, vasculitides, and/or hematogenous infections. The clinical features of AoFs are often nonspecific, with patients presenting with bleeding manifestations, back or abdominal pain, fever, and shock. Confirmation with invasive endoscopy is often impractical in the acute setting. Imaging plays an important role in the management of AoFs, and multiphasic multidetector CT angiography is the initial imaging examination of choice. Obvious signs of AoF include intravenous contrast material extravasation into the fistulizing hollow organ, tract visualization, and aortic graft migration into the adjacent structure. However, nonspecific indirect signs such as loss of fat planes and ectopic foci of gas are seen more commonly. These indirect signs can be confused with other entities such as infection and postoperative changes. Management may involve complex and staged surgical procedures, depending on the patient's clinical status, site of the fistula, presence of infection, and anticipated tissue friability. As endovascular interventions become more common, radiologists will need to have a high index of suspicion for this entity in patients who have a history of aneurysms, vascular repair, or trauma and present with bleeding. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ^©RSNA, 2021.