C19 - Patent Ductus Arteriosus Characterized by Transesophageal Echocardiography in Dogs

Abstract:

Background: Patent ductus arteriosus (PDA) morphology in dogs has relied primarily on angiographic description. Transesophageal echocardiography (TEE) provides unique imaging capabilities.

Objective: Characterize PDA based on TEE description. Animals: 299 client-owned dogs.

Methods: Retrospective review of TEE imaging studies to obtain measurements of pulmonary ostium diameter, ampulla length, ampulla width 4mm above the ostium and at aorta level, and to describe ductal shape, unique characteristics, and unusual morphologies.

Results: The most common breeds were mixed (Nf36), German shepherd (Nf33), Labrador retriever (Nf16), and Australian shepherd (Nf15) with a female to male ratio of 204 to 95. Mean ostium diameter was 3.3mm (SD 1.5; range, 0.6-9.1mm). In the majority of dogs, the PDA tapered to an ostium with varying ostium to ampulla ratios (267 < 50%; 32 > 50%) and with combinations of short and long ampullas based on a length to width 4mm above the ostium ratio (52 < 1.0; 239 > 1.0; Nf291). Additional observed characteristics included the presence of constrictions within the ampulla in 22 dogs, some of which were in the location of device landing zones, and ampulla motion that could be characterized as an extension or expansion throughout the cardiac cycle. Conclusions and Clinical Importance: Information from TEE imaging can aid in refining the current angiographic derived PDA morphology scheme. Imaging with TEE provides an opportunity to make specific measurements and observations about PDA characteristics that can provide valuable information when selecting the best closure method for an individual dog.