Pulmonary Artery Mass Caused by Aspergillus fumigatus Infection After Heart Transplantation: A Case Report.

Background: Invasive aspergillosis (IA) is a severe complication after solid organ transplantation, especially in patients receiving long-term immunosuppressive therapy. Pulmonary artery involvement caused by Aspergillus fumigatus is extremely rare and may mimic pulmonary artery thrombosis or malignancy, resulting in diagnostic challenges. Case Presentation: A 61-year-old male developed fatigue, intermittent fever, cough, and chest discomfort seven months after orthotopic heart transplantation. Computed tomography pulmonary angiography revealed a mass-like filling defect involving the main pulmonary artery and left pulmonary artery, which was initially suspected to represent pulmonary artery thrombosis or tumor. Whole-blood next-generation sequencing identified Aspergillus fumigatus and Streptococcus mitis. The patient was treated with voriconazole, anticoagulation therapy, and adjustment of immunosuppressive therapy. Follow-up imaging demonstrated progressive regression of pulmonary artery lesions and disappearance of pulmonary nodules without evidence of graft rejection. Conclusions: Pulmonary artery aspergillosis should be considered in heart transplant recipients presenting with pulmonary artery-occupying lesions, particularly when imaging findings are atypical. Early pathogen identification combined with appropriate antifungal therapy, individualized immunosuppression adjustment, and careful monitoring may improve clinical outcomes.