Aorto-atrial fistula formation and closure: a systematic review

Blood flow between the aorta and atrium is a rare but complex pathological condition, also known as aorto-atrial fistula (AAF). The exact incidence of this condition is unknown, as are the major precipitating factors and best treatment options. We carried out a systematic review of the available case report literature reporting AAF. We systematically reviewed literature on AAF formation and closure. Separate Medline (PubMed), EMBASE, and Cochrane database queries were performed. The following MESH headings were used: atrium, ventricle, fistula, cardiac, shunts, aortic, aorto-atrial tunnels and coronary cameral fistula. All papers were considered for analysis irrespective of their quality, or the journal in which they were published. Fistula formation from the ascending aorta to the atria occurred more often in the right atrium compared to the left. Endocarditis was the major cause of AAF formation, whilst congenital causes were responsible for nearly 12%. In a number of cases fistula formation occurred secondary to cardiac surgery, whilst chest traumas were a relatively rare cause of AAF. Correction via an open surgical approach occurred in 73.5% of cases, whilst percutaneous intervention was utilised in 10% of patients. In 74.3% of all studied cases the fistula repair was successful and patients survived the procedures. In 14.7% of the cases patients did not survive. Similar outcomes were observed between percutaneous and surgical interventions. Data from larger populations with AAF is lacking, meaning that specific data regarding incidence and prevalence does currently not exist.