A pacemaker is a 20-50g device inserted in the chest to correct a very slow heartbeat. The pacemaker emits electrical impulses that control the heart, preventing an irregular heartbeat. A pacemaker is comprised of a computer circuit and battery (pulse generator), so insertion of the device is a relatively straightforward procedure. Wires (pacing leads) help connect the device to the heart so impulses can travel to the heart directly. 

The electrical impulses travel through wires attached to the heart. As a result, the rate at which the electrical impulses travel is referred to as the pacing rate. Modern pacemakers are programmed to function according to your heart’s rhythm. Therefore, signals are sent at a steady pace to help correct an irregular heartbeat.

An implantable cardioverter defibrillator (ICD) is a device that works just like a pacemaker. Still, it transmits a larger electrical shock to reboot the heart and help get it pumping again, this time at a regular pace. An ICD is recommended for patients at risk of cardiac arrest. When an ICD senses the heart is beating unusually, it emits an electric shock that corrects the pace at which the heart beats.

Essentially, the heart is a muscle pump whereby the function is regulated by electrical signals sent from a pacemaker or ICD or sometimes both a pacemaker and ICD.

How does Dr Hassen insert a pacemaker?

Dr Hassen creates a 6 - 10cm incision beneath the collarbone on the left side, where he inserts the pacemaker wires into a vein. He uses x-ray imaging to guide the pacing leads into the heart’s chamber through the vein. Then, he lodges them into the heart’s tissue. The ends of the wires are attached to the pacemaker that fits into a pocket between the upper portion of the chest and chest muscle.

Transvenous implantation is done while you are under local anaesthetic, which is delivered via injection. The procedure can take one hour or more, depending on whether you have a biventricular pacemaker fitted.

Epicardial implantation is rarely performed but is still an option for patients. For this procedure, the pacing leads are connected to the heart’s surface (epicardium) via an incision through the abdomen beneath the chest. The pacemaker rests in a pocket made beneath the surface of the skin in the abdomen. Epicardial implantation is performed on paediatric patients and those who have just undergone heart surgery.