Left Ventricular Reverse Remodeling After Ductal Closure in Dogs with Hemodynamically Significant Patent Ductus Arteriosus

The purpose of the present study was to evaluate whether or not preoperative clinical parameters could predict left ventricular reverse remodeling in dogs who underwent successful patent ductus arteriosus (PDA) closure. Thirty-nine client-owned dogs diagnosed as PDA with left ventricular dilation were used. Increased left ventricular internal dimension index and decreased fractional shortening acquired before the ductal correction were identified as the independent predictors of short-term regression of left ventricular dilation. Therefore, left ventricular dilation and decreased systolic function prior to ductal closure may predict failure of early post-operative left ventricular reverse remodeling. INTRODUCTION Patent ductus arteriosus (PDA) with left-toright shunting causes volume overload of the left side of the heart, resulting in eccentric hypertrophy of the left side of the heart. The heart size and function were expected to return to a normal reference range after the successful closure of the PDA. However, it has been reported that the persistence of abnormal systolic indices as well as cardiomegaly after the closure are commonly seen.1 This phenomenon could be due to changes in hemodynamics and/or impaired cardiac function subsequent to cardiac remodeling. Persistent cardiomegaly and myocardial dysfunction cause clinical signs and even death in some dogs after ductal closure. There is ample evidence available supporting the PDA closure as a curative measure. However, it is unclear who is predisposed to fail after short-term reverse cardiac remodelLeft Ventricular Reverse Remodeling After Ductal Closure in Dogs with Hemodynamically Significant Patent Ductus Arteriosus