Cardiac Pacemaker Implantation/ICD/CRT

Traditional cardiac pacemakers are generally implanted if the heart rate is too low (bradycardic arrhythmia). This is usually the consequence of a disease in the coronary arteries, myocardium or heart valves causing isolated damage to the conduction system. Bradycardia which occurs spontaneously and for no obvious reason is less common. Depending on the nature of the arrhythmia, either a single-chamber or a dual-chamber cardiac pacemaker is implanted. The single-chamber pacemaker has one electrode, which is generally implanted in the right ventricle. A dual-chamber pacemaker has two electrodes, which are implanted in the right atrium and right ventricle of the heart.

An ICD usually has either one or two electrodes. It is used to shock the heart to suppress ventricular fibrillation or ventricular flutter, i.e. when the heart rate is either too fast or not beating synchronously. Ventricular fibrillation/flutter is an acute, life-threatening condition. By administering a shock, the fibrillation can be terminated. Ventricular fibrillation is usually a consequence of substantial damage being caused to the myocardium by a disease affecting the coronary arteries or the myocardium itself (cardiomyopathy). Such diseases reduce the ability of the heart to work efficiently. If performance falls below 30%, then the risk of ventricular fibrillation rises markedly. This can be prevented by implanting an ICD. An ICD can also perform the tasks of a 'traditional' cardiac Pacemaker.

A number of disorders can result in asynchronous contraction of the chambers of the heart. These include damage to the coronary arteries or the myocardium after a heart attack. The heart beat can be resynchronized using a cardiac pacemaker with a cardiac resynchronization therapy (CRT) function, and the efficiency of the heart improved. A CRT system has three electrodes which are applied to different areas of the heart. In addition to the CRT function, this cardiac pacemaker can also perform the tasks of a 'traditional' cardiac pacemaker.

On the day of your admission to a general ward, you will be questioned in detail, your paperwork will be examined, and any outstanding tests will be conducted, e.g. blood tests, X-rays or ultrasound examinations. Once all of your paperwork and tests are complete, you will discuss the operation you require with the surgeon and the anesthetist. The operation will take place the next day. It will normally be performed under local anesthesia, i.e. general anesthesia is not necessary. An incision is made under the left or right clavicle, and the cardiac pacemaker is inserted into the pocket which is opened in the skin tissue. The electrodes are inserted into the heart by puncturing a vein beneath the clavicle. Once the pacemaker has been tested to ensure it is functioning well, the skin is carefully closed. You will then be returned to the general ward. You will normally spend 1 or 2 days in hospital.