Silent growth of multiple giant coronary artery aneurysms in eosinophilic granulomatosis with polyangiitis

A 75-year-old woman with eosinophilic granulomatosis with polyangiitis (EGPA) underwent routine annual chest radiography. EGPA had been diagnosed 11 years earlier and was apparently controlled with immunosuppressive therapy, including mepolizumab. She had no chest pain, dyspnoea, elevated inflammatory markers, or new electrocardiographic changes. Serial chest radiographs showed progressive protrusion of the left cardiac border, evident on the current radiograph (Panel A) and first subtly visible 3 years earlier. Contrast-enhanced computed tomography revealed multiple giant coronary artery aneurysms involving the left main, left anterior descending, circumflex, and obtuse marginal arteries, with a maximum diameter of 42.5 mm (Panel B). Three-dimensional computed tomography angiography demonstrated the overall spatial configuration of the aneurysmal left coronary system (Panel C). Coronary angiography was performed for further anatomic assessment, but contrast dilution within the large aneurysmal sacs limited visualization of the inflow and outflow vessels and the relationships among the aneurysms (Panel D). Because of the aneurysm size, multiplicity, and concern for rupture or thrombotic complications, surgical aneurysm exclusion with coronary artery bypass grafting was performed. Histopathological examination revealed elastic fibre loss in the aneurysmal wall and focal disruption of the internal elastic lamina in the vasa vasorum, suggesting vasculitic coronary injury.