Clinical analysis and predisposing factors of canine heartworm
canine, cardiorespiratory, heartworm, zoonosis.
Canine heartworm is an important cardiorespiratory parasitic disorder, whose etiological agent is the filarid Dirofilaria immitis. Its impact on animal health is relevant due to its pathogenicity and growing worldwide distribution. Canids are the definitive hosts to which the filarid is best adapted and the Culicidae mosquitoes the effective intermediate hosts. The main habitat of D. immitis is the pulmonary arteries, although adult parasites can be found in the right heart chambers or even in the vena cava. Clinical signs are related to parasitic load, time of infection and physical activity, and definitive host immune response. The most common clinical signs are: i) exercise intolerance, ii) cough, iii) anorexia, iv) weight loss, v) prostration, vi) signs of right congestive heart failure, and vii) syncope. Cardiopulmonary assessments should be performed by chest radiography and Doppler echocardiography. In order to evaluate the clinical behavior of the infection, dogs naturally infected by D. immitis attended at the Cardiology and Respiratory Diseases Service of the Small Animal Sector of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro from October 2019 to December 2019 will be included in the study, as well as a retrospective study analyzing the medical records of dogs treated at the service from March 2017 to September 2019. Physical examination, laboratory tests (blood count, microfilariae research and D. immitis antigens) and complementary exams (CXR and Doppler echocardiography), as well as analysis of predisposing factors (gender, race, age, size, coat and place of residence of dogs) and clinical (clinical signs and alterations in the complementary exams). ).