A pacemaker is an electronic therapeutic device that is implanted in the body. It is designed to treat cardiac dysfunction due to certain cardiac arrhythmias by delivering electrical impulses energized by a battery through a pulse generator, which is transmitted through a wire and electrodes to stimulate the myocardium that the electrodes come in contact with, causing the heart to thrill and contract. The pulse generator delivers pulses of a certain frequency at regular intervals, which are transmitted through the wires and electrodes to the myocardium contacted by the electrodes, so that the local myocardial cells are stimulated by the external electrical stimulation and become excited, and then conduct to the surrounding myocardium through the intercellular gap connections or intercalary disk connections, resulting in the excitation of the whole atrium or ventricle, which in turn leads to contraction activity.
It is important to emphasize that the myocardium must have excitation, conduction, and contraction in order for cardiac pacing to work. Artificial cardiac pacing systems consist of two main components: the pulse generator and the electrode leads. The pulse generator is often referred to as the pacemaker alone. The electrode lead is an electrically conductive metal wire wrapped in an insulating layer, whose function is to transmit the electrical impulses from the pacemaker to the heart, and to transmit the heart's intracavitary electrocardiogram to the sensory circuits of the pacemaker. The pacing electrode wires are placed for a period of time generally not exceeding 2 weeks, and the pacemakers are placed outside the body, and the pacing electrode wires are withdrawn immediately after diagnostic, therapeutic, and prophylactic purposes have been achieved.
Permanent pacemakers should be considered if continued pacing therapy is required. Patients with any symptomatic or hemodynamically altered bradycardia are candidates for temporary cardiac pacing. The purpose of temporary cardiac pacing is usually categorized as therapeutic, diagnostic, and prophylactic. The femoral, subclavian, or internal jugular vein puncture is usually used to deliver the temporary pacing electrode lead.
Displacement of the electrode lead is more common than with permanent cardiac pacing. Postoperative electrocardiographic monitoring should be intensified, including early elevation of pacing thresholds, changes in perceived sensitivity, and electrode lead dislocation, especially in pacemaker-dependent patients. In addition, since the electrode lead is connected to the outside world through the puncture point, care should be taken to clean the area and avoid infection, especially in those who have been placed for a long time. In addition, after temporary pacing via the femoral vein the patient should be kept in a flat lying position, with the lower limb on the side of the vein puncture braked.