Basic Concept of Atrial Fibrillation Atrial fibrillation (AF) is the most common persistent arrhythmia, with an incidence rate of more than 5% in older people over the age of 65. Atrial fibrillation not only makes patients feel panic, shortness of breath, chest tightness, fatigue, mental depression obviously affects their normal work and life, but also makes the original heart failure and angina symptoms aggravate, long-term atrial fibrillation or frequent atrial fibrillation is also prone to lead to stroke, resulting in hemiplegia. The harm of atrial fibrillation has three main aspects: 1, affecting the quality of life: patients with palpitations, chest tightness, dizziness and other symptoms; 2, increasing the risk of thromboembolic events: can be manifested as hemiplegia (stroke), severe abdominal pain (mesenteric artery embolism) and limb blackness (limb artery embolism), etc.; 3, leading to changes in the structure of the heart: long-term atrial fibrillation can cause cardiac enlargement, leading to or exacerbating heart failure. Which patients are suitable for atrial fibrillation catheter ablation? Paroxysmal or persistent atrial fibrillation with frequent attacks or short duration, which significantly affects the quality of life; 2. Ineffectiveness of more than one kind of antiarrhythmic drugs, or intolerance of antiarrhythmic drugs (side effects occur), or unwillingness to medication; 3. Absence of significant left atrial enlargement (diameter of the left atrium is <50mm, preferably less than 45mm); 4. Absence of serious organic heart disease such as severe valvular disease 4, no serious organic heart disease such as severe valvular disease, pulmonary hypertension, or the cause of organic heart disease has been lifted, such as after valve replacement; 5, the general requirement is that the age is less than 75 years old, and patients older than 75 years old can also do atrial fibrillation catheter ablation if they are in good general condition. Which patients are not suitable for atrial fibrillation catheter ablation? Patients with thrombus in the left atrium; patients with serious systemic diseases, such as advanced tumor, abnormal coagulation function, lung failure and other important organ failure; elderly patients and the systemic condition can not tolerate the procedure; other patients, such as those who do not accept atrial fibrillation catheter ablation. Principles of Atrial Fibrillation Catheter Ablation Recent studies on the mechanism of atrial fibrillation have shown that the onset and maintenance of atrial fibrillation is closely related to the release of rapid electrical activity from one or more foci within the heart. These abnormal electrical activities of the heart are characterized as atrial premature beats (APBs) if they emit only a single excitation, and disorganized atrial tachycardia or atrial fibrillation if they emit a series of rapid excitations, which is why many patients with atrial fibrillation have a combination of atrial tachycardia and atrial fibrillation. Atrial fibrillation catheterization is based on the principle that the catheter is delivered to the site of these lesions, and the electrodes at the head of the catheter transmit electrical energy into thermal energy to encircle and destroy these lesions. Since the vast majority of these lesions are located in the pulmonary veins connected to the heart (each person usually has 4 pulmonary veins, 2 on each side), catheter ablation of atrial fibrillation is now also known as electrical isolation of the circumflex pulmonary veins. Advantages of catheterized eradication Medication is the treatment being used by the vast majority of patients with atrial fibrillation at this stage, but this treatment is overall less effective. If drugs are used to reverse atrial fibrillation and maintain sinus rhythm (i.e., normal rhythm), the sinus rhythm maintenance rate is only about 40% after 2 years, and the best drug for atrial fibrillation at this stage, ketorolac (amiodarone), has a 4-year discontinuation rate of up to 19% due to side effects; if drugs are used to control the ventricular rate, although it can be controlled in most patients' ventricular rate in a better range, atrial fibrillation is not eliminated, which means that atrial fibrillation thrombosis is not eliminated. This means that the risk of thromboembolic complications from atrial fibrillation remains. Pharmacologic treatment of AF also includes an important warfarin anticoagulation therapy, and although the risk of stroke complications can be reduced by two-thirds with regular use of anticoagulants, regular (weekly) monitoring of the intensity of anticoagulation is required, as the patient's risk of bleeding complications increases significantly in the event of anticoagulant intensity overload. The greatest advantage of catheterization over pharmacologic therapy is that if the procedure is successful, it is possible to eradicate AF completely (the success rate of involvement is about 80% to 85%, and the rate of serious complications is less than 0.5%), and there is no need for antiarrhythmic medications, so if catheter ablation is successful, this is a once-and-for-all procedure. What to know in the perioperative period of AF catheterization In addition to some routine tests, there is another necessary test to be done before AF catheter ablation - transesophageal echocardiogram. The purpose of transesophageal echocardiogram is to rule out atrial thrombus, and if there is an atrial thrombus, anticoagulation will be needed to melt it before proceeding with the procedure. The time to perform a radical AF catheterization is usually 3 to 4 hours, with a preoperative preparation time of about 30 minutes. The patient is awake during the procedure (some patients can be put under general anesthesia if they wish). Some patients experience some pain during catheter ablation, and the surgeon usually gives the patient a small amount of analgesic medication in advance so that the pain is eliminated or reduced. Bed rest is required for 24 hours after the procedure. Three months after the operation, due to the atrial muscle edema and endothelialization incompletion after ablation, some patients may have postoperative arrhythmia, such as atrial flutter, atrial fibrillation, or atrial premature, etc. Therefore, it is necessary to take anticoagulant and antiarrhythmic drugs in the postoperative period of 2-3 months, and then all the medicines can be discontinued if there is no recurrence of the arrhythmia. The total hospitalization time is usually about 1~2 weeks. Some patients require more than 2 ablations Atrial fibrillation pulmonary vein isolation is more complicated than supraventricular catheter ablation, and the success rate is lower than that of supraventricular catheter ablation (supraventricular catheter ablation can reach more than 95%), therefore, some patients need to undergo re-catheterization due to recurrence, which is mainly due to the resurfacing of the original lesions and the emergence of new lesions. The main reasons for recurrence are the "revival" of existing lesions and the emergence of new lesions. Given that current technology cannot guarantee that all AF foci can be eliminated or isolated in a single procedure for each patient, some patients may experience recurrence of AF after the procedure. It should be noted, however, that unlike other arrhythmias, it takes 2 to 3 months to determine the effect of catheterization of AF (due to the fact that it takes 3 months for atrial myocardial edema to subside after ablation). Therefore, the onset of atrial fibrillation or atrial flutter within 3 months after the procedure does not mean that the arrhythmia has really recurred. In most patients, the arrhythmia disappears as the atrial myocardial edema subsides, but if the arrhythmia does not disappear after 3 months, then the arrhythmia is defined as a recurrence of atrial fibrillation, and reablation is required.