I often get questions from patients about my ECG and my slow heartbeat, do I need a pacemaker or not? In my article “How do pacemakers work? In the article “How do pacemakers work?”, I introduced the pacemaker principle and what pacemakers actually do. To put it simply, a pacemaker is needed when a slow heartbeat does not meet the body’s blood supply needs or when the heart is in danger of stopping. This means that if the heart’s engine fails, or if the heart’s electrical conduction fails, an artificial pacemaker is needed to help stimulate the heart to beat in order to avoid life-threatening conditions. A problem with the heart’s engine. This is often referred to as sick sinus node syndrome, where severe sinus bradycardia, sinus block, sinus arrest, etc. occur. Usually, a pause greater than 3 seconds is dangerous. In case of a slow heartbeat caused by simple sinus bradycardia, say around 40 beats/min, if there are no symptoms such as dizziness, blackness, fainting, etc., a pacemaker is usually not necessary. Be aware that the heartbeat would have been slower at night and can be observed if there is no long interval of more than 3 seconds. If there are symptoms such as dizziness, blackness, fainting, etc., and they are proven to be related to a slow heartbeat, then a pacemaker should be installed. There is a special case of atrial fibrillation. There are already long intervals in atrial fibrillation. How there is a long interval of 5 seconds or more and the heart stops beating, then a pacemaker must be installed. If it is less than 3 seconds, installation is generally not needed. 3-5 seconds, a specific analysis is needed and can generally be observed. There is a problem with the conduction circuit of the second heart. The main problem is atrioventricular conduction block. There are three degrees of block: first degree, second degree (divided into type I and type II), and third degree. A pacemaker is required when second degree type II and third degree AV block has occurred. Note that first-degree and second-degree type I (often physiologic) AV block do not require a pacemaker. It is worth noting that when the above malfunctions are irreversible (e.g., congenital, aging, surgical injury and ischemic injury over a long period of time), a permanent pacemaker is required, i.e., the pacemaker is buried in the body (usually under the skin in the chest). If these changes are estimated to be reversible, a temporary pacemaker can be installed if the heartbeat is slow, i.e. the pacemaker is placed outside the body and the electrode leads are placed inside the body. When the malfunction improves, the temporary pacemaker can be withdrawn. It is not necessary to install a permanent pacemaker. The reversible causes of these temporary pacemakers are: 1) acute myocardial ischemia (including acute myocardial infarction); 2) acute myocarditis; 3) electrolyte disturbances (including uremia); 4) drug overdose; 5) vagal excitation; 6) catheter injury and early surgical injury When these conditions are corrected, most heartbeats can be restored. If this is not possible, then a permanent pacemaker may be required. There are also special cases where a pacemaker can be installed to help the heart, such as certain severe heart failure (with a three-chamber pacemaker), cardiac arrest, and severe ventricular arrhythmias (with a defibrillator). Even an artificial heart can be installed.