Dual chamber pacemaker with leads seen on a chest x-ray PA view. The pulse generator consists of battery and circuitry. The circuitry controls and monitors the function of the pacemaker. It can also transmit the data using radiofrequency signals to a programmer head kept over the pacemaker. Two leads are connected to the pacemaker (pulse generator) and firmly fixed in situ by screws. The pulse generator position is a little down because of sagging within the pacemaker pocket as the subcutaneous tissue is lax. The two leads fixed to the connectors can be seen coursing up to enter the subclavian vein and hence into the innominate vein, superior vena cava and the right atrium. The atrial lead terminates in the right atrium while the ventricular lead can be traced further down. Usually the atrial lead is kept in the right atrial appendage while the ventricular lead is kept at the right ventricular apex. If there is difficulty in anchoring, a screw in lead can be used. A more penetrated view will be needed (or image intensifier fluroscopy) to see the actual lead tips and the entire intra cardiac course of the leads. Magnified fluroscopic views are useful to look for lead fractures.