Open atrial septal defect repair in a dog using fresh autologous pericardium

A one-year-old Standard poodle was presented for evaluation of exercise intolerance with suspicion for a large atrial septal defect. Transthoracic echocardiography identified an unrestricted 2-cm secundum-type atrial septal defect with a peak left-to-right flow of 1 m/s yielding a Qp/Qs ratio of 2.1:1 and moderate right-sided chamber dilation. Based on clinical signs and echocardiographic findings, closure was recommended. Transesophageal echocardiography was subsequently performed to help determine the most appropriate closure method, which revealed insufficient posterior rim, and hence, surgical repair was recommended. The defect was closed using fresh autologous pericardium under normothermic cardiopulmonary bypass. Surgery and immediate postoperative recovery were relatively uncomplicated. Intra-operative epicardial and postoperative transthoracic echocardiography showed no residual atrial septal defect. The patient was closely monitored in the intensive care unit until discharge eight days after the procedure with no cardiac medications. Follow-up echocardiogram was performed three weeks postoperatively, showing an intact patch, no evidence of interatrial shunting, and decrease in right-sided chamber size. At six months, echocardiography showed an intact septum, normal right atrial and ventricular size, and resolution of clinical signs. This is the first known report of the use of fresh autologous pericardium as a durable and safe patch choice for atrial septal defect repair in a dog. Autologous pericardium is cost-effective and readily available. It is commonly employed to repair many cardiovascular defects in humans including atrial septal defects, right ventricular outflow tract enlargement, and pulmonary artery augmentation. This report also highlights the benefit of multimodal imaging in clinical decision-making.