Radiographic features of cardiogenic pulmonary oedema in dogs with dilated cardiomyopathy

Objectives Dilated cardiomyopathy (DCM) is a common cause of acquired cardiac disorder in dogs, second only to myxomatous mitral valve disease (MMVD). This study aimed to describe the thoracic radiographic features of cardiogenic pulmonary oedema in dogs with DCM. Materials and Methods Thoracic radiographs of dogs in left‐sided congestive heart failure with an echocardiographically confirmed diagnosis of DCM were included in this retrospective study. Radiographs were retrospectively reviewed by two radiologists to assess the distribution, severity and characteristics of the pulmonary pattern, as well as to identify the presence of pleural effusion and degree of cardiomegaly. Results A total of 97 dogs with L‐CHF due to DCM met the inclusion criteria. Results of the study suggest that the predominant pulmonary pattern differs from myxomatous mitral valve disease and is characterised by a mild to moderate (62/97 or 63.9% and 30/97 or 30.9%, respectively), unstructured interstitial (72 or 74.2%), diffuse (90 or 92.8%) and predominantly ventrally distributed (52 or 53.6%) pulmonary pattern. A subset of dogs (49 or 50.5%) had diffusely distributed linear soft tissue opacities throughout all lung lobes considered to represent pulmonary vascular congestion, bronchial cuffing and/or thickening of the bronchi. Clinical Significance The pulmonary pattern of L‐CHF with DCM differs from what has been previously reported for dogs with MMVD. The predominant pulmonary pattern with L‐CHF in dogs with DCM was a diffuse, marked, more severely ventrally distributed, mild to moderate, unstructured interstitial pulmonary pattern.