Diagnosis and Therapeutic Management of Dilated Cardiomyopathy in Canines

Abstract

Background: Dilated cardiomyopathy (DCM) is a myocardial disorder characterised by ventricular chamber dilatation and impaired systolic function. Aims: This study investigated the prevalence, diagnostic characteristics, and therapeutic management of canine cardiac disorders, with particular emphasis on DCM. Methods: A total of 3,331 dogs presented to the Veterinary Clinical Complex, College of Veterinary Science and Animal Husbandry, Nanaji Deshmukh Veterinary Science University (NDVSU), Jabalpur, Madhya Pradesh, during the study period. Of these, 123 dogs with clinical signs suggestive of cardiac disease underwent clinical examination, electrocardiography (ECG), and serum cardiac biomarker estimation. Thoracic radiography and echocardiography were performed in dogs with abnormal ECG findings and/or elevated biomarker concentrations. For the therapeutic study, eight dogs with echocardiographically confirmed DCM were randomly assigned to receive either pimobendan plus enalapril (G1) or digoxin plus enalapril (G2). Therapeutic response was evaluated echocardiographically on Days 15 and 30. Results: Cardiac disorders were confirmed in 57 of the 123 screened dogs. The most common ECG abnormalities were altered P wave (59.37%), low-voltage QRS complexes (34.61%), and tall T waves (30.00%). Mean serum cardiac troponin-I (2.39 ± 0.27 ng/mL) and CK-MB (81.99 ± 3.01 U/L) concentrations were significantly higher in affected dogs than in healthy controls (p < 0.05). Vertebral heart score was also significantly increased in affected dogs. Echocardiography identified DCM in 14.03% of affected dogs, followed by hypertrophic cardiomyopathy (8.77%) and pericardial effusion (5.28%). Dogs treated with pimobendan plus enalapril showed significantly greater improvement in ejection fraction and stroke volume on Day 30 than those receiving digoxin plus enalapril (p < 0.05). Conclusions: A multimodal diagnostic approach comprising ECG, cardiac biomarkers, radiography, and echocardiography effectively identified canine cardiac disorders. Pimobendan combined with enalapril provided superior improvement in cardiac systolic function compared with digoxin plus enalapril, supporting its use in the management of canine DCM.