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Prevalence of congenital heart disease in 76,301 mixed-breed dogs and 57,025 mixed-breed cats

Donald P. Schrope
Journal of veterinary cardiology 2015 v.17 no.3 pp. 192-202
cardiomyopathy, cats, disease prevalence, dogs, females, males, mixed breeds, patent ductus arteriosus, pulmonary artery, purebreds
Assess the prevalence of congenital heart disease (CHD) in a large population of mixed-breed dogs and cats.76,301 mixed-breed dogs and 57,025 mixed-breed cats.Retrospective review of records and examinations based on specified diagnostic criteria.Among mixed-breed dogs, the prevalence of CHD was 0.13% (51.4% female) and of innocent murmurs was 0.10% (53.0% male). Pulmonic stenosis was the most common defect followed by patent ductus arteriosus, aortic stenosis, and ventricular septal defect. Among mixed-breed cats, prevalence of CHD was 0.14% (55.2% male) and of innocent murmurs was 0.16% (54.4% male). When the 25 cats with dynamic left or right ventricular outflow obstruction were counted with cases of innocent murmurs, the overall prevalence was 0.2%. Ventricular septal defects were the most common feline CHD followed closely by aortic stenosis and hypertrophic obstructive cardiomyopathy. There was no overall sex predilection for CHD in mixed-breed cats or dogs, and no significant difference in CHD prevalence between cats or dogs. Among dogs, subvalvular aortic stenosis and mitral valve dysplasia had a male predisposition while patent ductus arteriosus had a female predisposition. Among cats, valvular pulmonic stenosis, subvalvular and valvular aortic stenosis, and ventricular septal defects had a male predisposition while pulmonary artery stenosis had a female predisposition.The prevalence of CHD in a mixed-breed dogs and cats is lower than for prior studies, perhaps due to the lack of purebreds in the study population or actual changes in disease prevalence.