When inserting a pacemaker there are two possible approaches: and with the codes divided according to the surgical approach?

There are two approaches used when inserting a pacemaker; the epicardial approach and the transvenous approach. Epicardial approach involves the opening the chest cavity and placing a lead on epicardial sac of heart while the transvenous approach involves accessing a vein and inserting an electrode into the vein. Epicardial approach for inserting pacemakers are divided based on approach to heart thoracotomy, upper abdominal or endoscopic.  

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