C09 - Demographic, Clinical and Echocardiographic Characteristics of Dilated Cardiomyopathy in Dogs Eating Hydrolyzed Diets

Abstract: Background - Diet-associated dilated cardiomyopathy (DCM) can occur in dogs eating high-pulse diets, and diet change can lead to clinical and echocardiographic improvements. There have been anecdotal reports of DCM in dogs eating hydrolyzed diets. Hypothesis/Objectives - To determine the prevalence and characteristics of dogs with DCM eating a variety of hydrolyzed diets. Animals - 2,222 dogs diagnosed with DCM. Methods - Medical records of dogs diagnosed with DCM at a nationwide cardiology specialty practice between May 2018-October 2023 were retrospectively reviewed. Demographic variables were compared between dogs eating hydrolyzed diets vs. non-hydrolyzed diets. Clinical and echocardiographic data were recorded. Results – Twenty-eight dogs (1.3%) were eating hydrolyzed diets prior to DCM diagnosis. The most common breeds were pit bull (n=6), English bulldog (n=4) and Doberman pinscher (n=4). Arrhythmias were seen in 17/28 dogs, and 17/28 dogs had congestive heart failure. Age (median=9.4 yrs; P=0.47), sex (19 male, 9 females; P=0.97), and body weight (median=33.2 kg; P=0.52) of dogs eating hydrolyzed diet were not statistically different from dogs eating non-hydrolyzed diets. Fourteen of the twenty-eight dogs had follow-up echocardiograms. For the five dogs that changed diet, there was a significant reduction in left atrial to aortic ratio (LA/Ao) at the follow-up exam (P=0.04), whereas there was no significant change in LA/Ao in the nine dogs that did not change diet (P=0.72). Conclusions and Clinical Importance – Dilated cardiomyopathy can occur in dogs eating hydrolyzed diets. The role of diet is unclear and warrants further investigation.