Comparative, multidimensional imaging of patent ductus arteriosus and a proposed update to the morphology classification system for dogs

Abstract

Background: Accurately assessing the morphology and shape of the patent ductus arteriosus (PDA) and obtaining measurements are important to avoid procedural complications. Objectives: To characterize and compare PDA morphology, shape, and dimensions with angiography and echocardiography. Animals: 25 client-owned dogs with echocardiographically confirmed PDA. Methods: Prospective case series. Imaging consisted of single plane angiography, transthoracic echocardiography from the right (TTE-R) and left (TTE-L), and two-dimensional, biplane, and three-dimensional transesophageal echocardiography (TEE-2D and TEE-3D). Measurements included angiographic minimal ductal diameter (MDD), echocardiographic pulmonary ostium in a single dimension (TTE-R, TTE-L, and TEE-2D) and in perpendicular dimensions (TEE-3D) with similar measurements of the ampulla 3 mm above the MDD or pulmonary ostium. The morphology and shape of the PDA were characterized. Results: Catheter-based occlusion (N = 20) and surgical ligation (N = 5) were performed without complication. Angiographic morphology was classified as type II (N = 19), type III (N = 1), and other (N = 1). Angiographic MDD and TEE-2D pulmonary ostium measurements were significantly (P =.008) but weakly correlated (r =.56); similar relationships were found for ampulla diameter measurements (P