Mycotic pulmonary artery pseudoaneurysm following total arch replacement: a case report

Background Although the true prevalence and incidence are not clearly known, mycotic pulmonary artery aneurysm is a potentially devastating condition that leads to high mortality, over 60% if untreated. Among them, mycotic pulmonary artery pseudoaneurysm, which occurs in relatively central areas, has rarely been reported. We report an extremely rare case of a late complication with a mycotic pulmonary artery pseudoaneurysm, presumably due to infective endocarditis, in a 68-year-old woman 4 months after total arch replacement. Case presentation A 68-year-old woman was referred to our department for 2 weeks with fever of unknown origin. She had a history of emergency total arch replacement for an acute type A aortic dissection 4 months earlier and chronic rheumatoid arthritis on monthly subcutaneous tocilizumab treatment for several years. Blood culture was positive for Enterococcus faecalis . Transthoracic and transesophageal echocardiography revealed a left ventricular ejection fraction of 58%, severe mitral regurgitation with a 15-mm diameter vegetation on the anterior mitral leaflet, and severe aortic insufficiency with string-like structures. Contrast computed tomography showed a focal saccular outpouching from the right pulmonary artery. On 18F-fluorodeoxyglucose (FDG) positron emission tomography, focal uptake of FDGs was observed along the same lesion of the pulmonary artery and ascending-arch graft. The patient eventually recovered after the surgical intervention of mitral and aortic valve replacement, re-total arch replacement, pulmonary artery repair, application of omental flap, and antibiotics without any evidence of re-infection after 1 year. Conclusions We report a successful surgical repair of mycotic pulmonary artery pseudoaneurysm 4 months after total arch replacement for acute type A aortic dissection. This report describes an effective treatment for an extremely rare postoperative condition.