FEMORAL-ARTERY OCCLUSION IN CAVALIER-KING-CHARLES SPANIELS

Objective - To investigate development of femoral artery occlusion in Cavalier King Charles Spaniels. Design - Prospective study. Animals - 954 Cavalier King Charles Spaniels. Procedure - 1,750 cardiovascular e xaminations consisting of visual inspection of mucous membranes, thora cic auscultation in areas associated with the heart valves, thoracic p alpation, and palpation of the femoral arteries were made at 10 dog sh ows on 954 dogs. Findings of clinically normal, weak, or undetectable femoral pulses were recorded. Pathologic changes in occluded femoral a rteries of 2 dogs were examined histologically. Results - Of the 954 d ogs, 22 (2.3%) had an undetectable right or left femoral pulse on 1 or more examinations. Forty (4.2%) additional dogs had weak unilateral o r bilateral femoral pulses. Only 1 dog had exercise intolerance, and i t had coexistent congestive heart failure. Histologic examination of s erial sections of an occluded femoral artery from 1 dog revealed intim al thickening with breaks in the internal elastic lamina proximal to t he occluded segment. The occluded segment of the femoral artery was co ntracted and filled with an organizing, recanalizing thrombus. Similar histopathologic changes were found in sections of a femoral artery fr om another dog. Clinical implications - Femoral artery occlusion is ra re in other breeds and is not clinically important in dogs because of adequate collateral circulation; however, its rather common developmen t in Cavalier King Charles Spaniels indicates a genetic predisposition and probable weakness in the femoral artery wall.