ULTRASONOGRAPHIC IDENTIFICATION OF DIROFILARIA-IMMITIS IN THE AORTA AND LIVER OF A DOG

A 5-year-old sexually intact male mixed-breed dog was evaluated becaus e of suspected vena caval syndrome secondary to heartworm disease. On physical examination, the dog was thin, icteric, and weak and had tach ycardia and a cardiac murmur. Serum biochemical and hematologic abnorm alities included hyperbilirubinemia, high serum alkaline phosphatase a nd alanine transferase activities, hypoalbuminemia, leukocytosis, and normocytic normochromic anemia. Dirofilaria immitis microfilariae were seen in a blood smear. Echocardiography was used to confirm the diagn osis of vena caval syndrome. Multiple aberrant adult heartworms were e vident ultrasonographically in the abdominal aorta and its branches an d within hypoechoic nodules in the left caudal lobe of the liver. The dog's condition deteriorated despite supportive treatment and retrieva l of 58 adult heartworms from the right side of the heart and vena cav a, and the dog was euthanatized. At necropsy, adult heartworms were fo und in the aorta and inflammatory hepatic nodules. To our knowledge, u ltrasonographic identification of heartworms within the systemic arter ial system and liver of a dog has not been described previously.