HEART AND LUNG SURGERY << BACK Temporary Pacemaker Placement A pacemaker is a small device that is permanently implanted near the heart. The device is battery-operated and is used to monitor the heart's electrical impulses. When needed, a pacemaker delivers an electrical impulse, or discharge, to make the heartbeat in a more normal rhythm. A temporary pacemaker is worn outside the body. It is used when a person is too sick to receive a permanent pacemaker, or when a person is likely to recover from a slow heart rate, making a permanent pacemaker unnecessary. Sometimes a temporary pacemaker is used in an emergency situation, such as low blood pressure. A temporary pacemaker is attached to the heart through a wire that is threaded through a neck vein. Temporary pacemakers are used only while a person is in the hospital.