3RD DEGREE ATRIOVENTRICULAR-BLOCK FOLLOWING NONPENETRATING CHEST TRAUMA IN A DOG

A two-year-old mixed breed dog was referred to the University of Flori da Veterinary Medical Teaching Hospital for the management of post tra umatic ventricular arrhythmias. Electrocardiography revealed third deg ree atrioventricular (AV) block. An echocardiogram demonstrated an ech ogenic, pedunculated mass arising from the caudoventral aspect of the atrial septum. The mass was believed to represent a haematoma or a thr ombus associated with trauma to this region of the atrial septum. The patient was managed conservatively; third degree AV block was still pr esent five days after trauma. The owner of the dog refused specific th erapy of the arrhythmia. The patient was discharged and, unfortunately , lost to follow-up. Third degree AV block has not previously been rep orted following accidental, blunt thoracic trauma in the dog.