Mycotic Pseudoaneurysm of the Ascending Aorta after Heart Transplantation

Introduction Mycotic pseudoaneurysm of the ascending aorta is a potentially fatal complication after heart transplantation (HTx). Pseudomonas (P.) aeruginosa as a pathogen is mainly seen in immunosuppressed patients. Possible symptoms are malaise, chest or thoracic back pain, dyspnea, dysphagia or fever. Occasionally asymptomatic cases are also reported. There is often a previous mediastinitis or other infection in the patient history. In our patient a P. aeruginosa pseudoaneurysm developed after HTx without any alarm symptoms. Case Report The 67-year-old male patient treated with hypertension, diabetes mellitus and chronic renal failure attended a regular visit five months after HTx. He was asymptomatic except of an unexplainable weight loss. Lab test showed a moderate C-reactive protein level elevation over the course of two months (4-7-24-57 mg/L), therefore further examinations were prepared to identify the source of infection. Transthoracic echocardiography, chest X-ray, abdominal ultrasound and urine culture revealed no abnormalities. Chest computed tomography (CT) however showed a significant (90 mm) saccular dilatation of the tubular portion of ascending aorta. No obvious concomitant infection was reported. An urgent surgical intervention was indicated. A pseudoaneurysm was identified intraoperatively starting at the aortic anastomotic suture line, it was successfully resected and the sinotubular junction was reconstructed with a vascular prosthesis. Cultures of the resected specimen grew P. aeruginosa while all blood cultures taken pre- and postoperatively remained negative. Histological examinations verified aortitis. The patient received 3 weeks of intravenous treatment with ceftazidim followed by long-term oral ciprofloxacin. 19 day postoperative CT revealed no sign of recurrent graft infection. 4 months after the operation the patient was asymptomatic with controlled blood pressure and normal inflammatory markers. Summary This case demonstrates the importance of considering a mycotic pseudoaneurysm of the aorta in the etiology of unexplainable inflammation following HTx. P. aeruginosa can be a causative organism which may indicate a long-term antibiotic therapy. It is important to check regularly the physical status, blood pressure, aortic diameters and inflammatory markers of the patient, as well as the potential side effects of antibiotic treatment.