A 31-year-old woman who had undergone left pneumonectomy for a tuberculosis-destroyed left lung 3 years previously presented in respiratory distress after a pregnancy complicated by preeclampsia and aspiration pneumonia. Investigation revealed a large aortic arch aneurysm as well as a filling defect in the descending thoracic aortic lumen. Emergency aortic arch reconstruction was performed for a massive pseudoaneurysm or contained rupture filling the entire postpneumonectomy space. Pathologic and microbiological examination demonstrated Aspergillus fumigatus and active inflammation.