Atrial fibrillation, referred to as “atrial fibrillation”, is a very common arrhythmia, ranking second only to premature beats, atrial fibrillation is the loss of the normal regular diastolic activity of the myocardium, replaced by rapid and uncoordinated weak peristalsis, resulting in the loss of the normal effective contraction of the atria, the electrocardiogram shows the disappearance of P waves, replaced by small f waves, with a frequency of about The ECG shows the disappearance of P waves, replaced by small f waves with a frequency of about 350 to 600 beats/min. Atrial fibrillation is divided into primary atrial fibrillation, paroxysmal atrial fibrillation, persistent atrial fibrillation, prolonged persistent atrial fibrillation, and permanent atrial fibrillation. Atrial fibrillation lasting more than 2 days has the potential for thrombosis, which can lead to embolic symptoms such as hemiplegia, aphasia, and coma. Cardiology transcatheter ablation for atrial fibrillation: A special catheter is inserted into the heart through a venous access and then sent to the corresponding part of the atrium where the abnormal electrical stimulation signal occurs under X-ray surveillance to eliminate these abnormal electrical activities through thermal damage such as radiofrequency to achieve the purpose of eliminating atrial fibrillation, and the mainstream procedure is circumpulmonary vein ablation. With the development of three-dimensional electrophysiological marker systems (such as the Carto system), cardiology catheter ablation for atrial fibrillation has become the first-line treatment modality at home and abroad (the latest AHA 2011 guidelines are the first class of recommended indications). For paroxysmal AF, the success rate of radiofrequency ablation treatment under the guidance of 3D system can reach more than 80%-90% in our center, and 70%-80% for chronic AF. INR monitoring in patients after AF ablation: One of the most common methods of anticoagulation in patients with AF catheter ablation is the oral anticoagulant warfarin, whose degree of anticoagulation is expressed by the International Normalized Ratio (INR). the monitoring of INR is very important for guiding patients to rationalize medication and avoiding the risk of bleeding or thrombosis. the INR is usually maintained around 2.0.