Calcified Dirofilaria immitis Mimicking Thoracic Foreign Body in a Dog

다국어 초록 (Multilingual Abstract)

A 13-year-old neutered male Pomeranian, weighting 3 kg, presented with respiratory distress and depression. Radiographic examination revealed calcified ring-like opacities in the main pulmonary artery, mimicking thoracic foreign bodies. Additionally, right heart and main pulmonary artery enlargement and notable lung infiltrations were also observed. Echocardiography showed coil shaped structures in the main pulmonary artery with increased echogenicity compared to other nearby heartworms, which is consistent with calcified Dirofilaria immitis (heartworms). The dog was diagnosed with caval syndrome, which is the advanced and severe manifestation of heartworm infection. This report presents a rare case of calcified heartworm infection observed during a radiological examination, which resemble foreign bodies. Therefore, chronic heartworm disease should be considered as a differential diagnosis when radiopaque ring-like opacities are observed in the pulmonary artery on thoracic radiographs.