Case Report: Long-Term Management of Imidacloprid-Moxidectin in a Dog with Caval Syndrome


  • Panyakamol Chandrasakha Faculty of Veterinary Science, Mahidol University
  • Rungrote Osathanon Faculty of Veterinary Science, Mahidol University
  • Namphung Suemanotham Faculty of Veterinary Science, Mahidol University


caval syndrome, canine heartworm, long term macrocyclic lactone


Caval syndrome is a condition from heavy heartworm infestations, causing intracardiac obstruction, potentiating in multiple fatal complications, and poor prognosis. Early diagnosis is imperative for prompt treatment and echocardiography has the benefit of aiding in exploring the cardiac structure and the worm burden. According to The American Heartworm Society guideline (2020), it has established several treatment regimens both medical and surgical. The purpose of this case report is to determine the clinical efficacy of long-term macrocyclic lactone in the treatment of heartworm in a dog with caval syndrome. An 8-year-old female French bulldog was presented with ascites. Numerous heartworms were detected intracardiac from an echocardiography. A monthly application of 10% imidacloprid and 2.5% moxidectin with 4 weeks of 10 mg/kg doxycycline had shown the efficacy in controlling heartworms of a dog with caval syndrome thus far, along with an exercise restriction to prevent complication from pulmonary thromboembolism. Reassessment of this patient was planned for a monthly health screening and a 3-month echocardiography for worms migration, thrombi, and antigen testing. After 3 months, the worms were unable to detect from echocardiography and the dog was no longer required abdominocentesis. The dog is currently living well and planned on giving a regular heartworm prevention program after 12 months.


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How to Cite

Chandrasakha, P. ., Osathanon , R. ., & Suemanotham, N. . (2022). Case Report: Long-Term Management of Imidacloprid-Moxidectin in a Dog with Caval Syndrome. Journal of Applied Animal Science, 14(2), 33–44. Retrieved from



Case report