ABSTRACT
Pacemaker therapy is indicated in veterinary medicine for symptomatic bradyarrhythmias including high-grade second-degree atrioventricular (AV) block, third-degree AV block, sick sinus syndrome, and persistent atrial standstill with a slow ventricular escape rate. Several types of pacemaker generators and pacing modalities are available. Electrodes may be unipolar or bipolar and can be implanted either on the epicardium or the endocardium. Before a permanent pacemaker is implanted, a complete cardiac work-up should be performed with thoracic radiographs, echocardiography, and an electrocardiogram. Intraoperative antibiotic therapy such as first-generation cephalosporin is recommended during pacemaker implantation to reduce the risk of implant infection. Permanent transdiaphragmatic pacemaker implantation is accomplished through a ventral midline celiotomy. The transvenous implantation is the less invasive technique and the method of choice. Pacemakers are usually set at an impulse rate between 80 to 100 beats/min according to the size of the dog and its activity level. Pacemakers can be reprogrammed for the rate, the output voltage, and the sensitivity by telemetry.
