Heart anatomy To understand arrhythmias one must first be generally familiar with the anatomy of the heart, which is located in the thoracic cavity, with 1/3 of the heart normally located on the right side of the thorax and 2/3 on the left side of the thorax. The normal heartbeat is located on the left side of the thorax, at the junction of the fourth rib space and the left midclavicular line. The heart is divided into atria and ventricles, where the atria include the left and right atria and the ventricles include the left and right ventricles. The normal heartbeat originates in the upper right part of the right atrium, the sinus node, where the excitation reaches the atrioventricular node (the junction between the atrium and the inner ventricle) along the intra-atrial conduction pathway, and then the excitation reaches the right and left ventricles along the bundle of Hitchcock and the left and right bundle branches. The heart begins the work of the cardiac cycle. What are arrhythmias? In layman’s terms, an arrhythmia is a heartbeat that is too fast, too slow, or too chaotic. A normal heartbeat (ventricular beat) is 60-100 beats per minute and usually has a regular rhythm, but teenagers may have an irregular heartbeat. A rapid heartbeat is a heartbeat of >100 beats per minute. Some arrhythmias have 150-250 beats per minute, such as paroxysmal supraventricular tachycardia; some arrhythmias have 100-250 beats per minute, such as ventricular tachycardia; some arrhythmias have 250-350 beats per minute, such as atrial flutter; and some arrhythmias have 350-600 beats per minute, such as atrial fibrillation. Slow heartbeat means heartbeat <60 beats per minute, such as sinus bradycardia, sinus arrest, atrioventricular block, etc. Excessive heartbeat means that the heartbeat becomes uneven, with a feeling of chaotic and missed beats. If premature beats appear, the heartbeat becomes untidy, atrial premature if it originates from the atria, ventricular premature if it originates from the ventricles, and atrial fibrillation also appears to have a more disorganized heartbeat; in the elderly, the arrhythmia that tends to appear is pathological sinus node syndrome, where the heartbeat can be fast or slow and the rhythm becomes untidy. Symptoms of arrhythmias The symptoms of arrhythmias are not specific and vary from person to person. For example, some people may have premature beats or atrial fibrillation for many years without symptoms and only find them during a physical examination. In some cases, even if there are only a few dozen or a few hundred premature beats per day, there is still a feeling of panic, chest tightness, stopping, or heartbeat loss, which seriously affects normal work, study and life. However, arrhythmias can also lead to serious symptoms, such as blackouts, syncope, and even sudden death. The presence of these symptoms generally indicates a serious condition, such as third-degree atrioventricular block, ventricular tachycardia, ventricular flutter or fibrillation, etc. Treatment of arrhythmias: Treatment of patients with tachyarrhythmias The aim of treatment is to slow down the heartbeat, and the main measures include: 1) Anti-arrhythmic drug therapy: such treatment measures can not only end tachyarrhythmic episodes, but also prevent them. Such as betalactam, cardioplegia, isoptin, lidocaine, adenosine, digoxin or amiodarone, etc., but must be applied under medical supervision. 2) Electrical cardioversion or defibrillation: Any patient with tachyarrhythmia with blood pressure falling to 90/60 mmHg, or with hemodynamic instability such as syncope, should be immediately electrically cardioverted to terminate the tachyarrhythmia attack, or electrically defibrillated to terminate the persistence of ventricular fibrillation. 3) Radiofrequency ablation: this treatment is a radical treatment measure, once the procedure is successful, you can say goodbye to the arrhythmia and do not need to take antiarrhythmic drugs to prevent recurrence. (4) ICD therapy: For patients with ventricular tachycardia or irreversible ventricular fibrillation caused by various reasons, once it occurs, hemodynamic instability or even syncope should be actively implanted with a cardioverter-defibrillator, i.e. ICD, which can quickly terminate the ventricular tachycardia or ventricular fibrillation attack. Treatment of patients with slow-beating arrhythmias Acute treatment consists mainly of medications to raise the heart rate, such as isoprenaline and atropine. Long-term treatment is the best treatment available due to the lack of effective therapeutic drugs, and artificial pacing therapy is the best treatment available. Implantation should be considered in patients with sinus arrest >3 seconds, atrial fibrillation >5 seconds and second degree type II or higher AV block. Treatment of patients with cardiac arrhythmias The treatment of patients with premature beats varies from person to person. For episodic atrial premature beats and ventricular premature beats, no treatment is generally required; for premature beats >10,000 beats per 24 hours, radiofrequency ablation or antiarrhythmic drugs can be considered; for premature beats with only a few thousand beats per 24 hours, no treatment can be given if there are no symptoms, but long-term follow-up is required, and antiarrhythmic drugs can be considered for those with symptoms. It is worth mentioning that premature ventricular contractions should be actively treated regardless of the number of contractions, as long as one of the following conditions occurs Patients with organic heart disease, cardiac insufficiency, family history of sudden death, history of syncope, and R on T phenomenon on ECG. In patients with atrial fibrillation, in addition to anticoagulation, patients with initial atrial fibrillation should try to restore sinus heartbeat (normal heartbeat); in patients with paroxysmal atrial fibrillation, if antiarrhythmic drug therapy is ineffective, radiofrequency ablation should be used to restore sinus heartbeat; in patients with persistent atrial fibrillation, sinus heartbeat should be restored as much as possible; in patients with persistent atrial fibrillation, active anticoagulation and ventricular rate control should be performed. Patients with atrial flutter should undergo radiofrequency ablation after 3 weeks of anticoagulation to restore sinus heartbeat. Patients with pathological sinus node syndrome, this arrhythmia often has fast heartbeat, slow heartbeat & chaotic heartbeat in the same patient. Treatment is usually pacing + antiarrhythmic drug therapy or pacing + radiofrequency ablation.