Quantitative Ablation of Pulmonary Vein Vestibule in Paroxysmal Atrial Fibrillation. (AI-ablation)

A Prospective,Single Center, Randomized Controlled Trial of Quantitative Ablation of Pulmonary Vein Vestibule in Patients With Paroxysmal Atrial Fibrillation..

The purpose of this trial is to explore the optimal AI value for isolating the pulmonary veins and achieving left ventricular apex and mitral isthmus block. Patients with atrial fibrillation who are scheduled to undergo catheter ablation will be randomized to different groups, then every group receive circumferential pulmonary vein isolation with different AI values. The relevant indicators such as the proportion of pulmonary vein single-circle isolation, operation time, the incidence of complications, and the proportion of recurrence of atrial fibrillation and other atrial arrhythmias after 1 year were collected.

This is a prospective, single-center, randomized controlled trial. In this part,a total of 90 patients with paroxysmal atrial fibrillation who are scheduled for catheter ablation were randomly divided into 3 groups, 30 patients in each group. For the first group, the AI target value for the front wall and the top wall is 550, and the rear wall and the lower wall are 400. For the second group, the AI target values for the front wall and the top wall are 500, the rear wall and the lower wall are 350. For the third group, the AI target values for the front wall and top wall are 450, the rear wall and the lower wall are 300. The pressure value at each point is 5-15 g, and the distance between adjacent ablation points is less than 5 mm. The relevant indicators such as single-circle isolation rate of the pulmonary vein, operation time, the left atrial operation time, and the supplemental ablation site are recoded. The incidence of intraoperative and postoperative complications such as stroke, pericardial tamponade and steam pop during ablation are observed. Dynamic electrocardiography is performed during the follow-up period to evaluate the proportion of sinus rhythm within 1 year.

Patients enrolled in the study were randomly assigned to different surgical groups using random envelopes. All study personnel were blind to treatment allocation and had no way of influencing whether a participant would receive high or low AI ablation.

In this group,patients with paroxysmal AF will receive pulmonary vein vestibule ablation with high AI value, the AI target value for the front wall and the top wall is 550, and the rear wall and the lower wall are 400.

In this group,patients with paroxysmal AF will receive pulmonary vein vestibule ablation with middle AI value, the AI target value for the front wall and the top wall is 500, and the rear wall and the lower wall are 350.

In this group,patients with paroxysmal AF will receive pulmonary vein vestibule ablation with low AI value, the AI target value for the front wall and the top wall is 450, and the rear wall and the lower wall are 300.

Patients with paroxysmal AF will receive pulmonary vein vestibule ablation with high AI value, the AI target value for the front wall and the top wall is 550, and the rear wall and the lower wall are 400.

Patients with paroxysmal AF will receive pulmonary vein vestibule ablation with middle AI value, the AI target value for the front wall and the top wall is 500, and the rear wall and the lower wall are 350.

Patients with paroxysmal AF will receive pulmonary vein vestibule ablation with low AI value, the AI target value for the front wall and the top wall is 450, and the rear wall and the lower wall are 300.

The number and location of the supplemental ablation required for pulmonary vein isolation after single-circle ablation

Diagnostic criteria for recurrence of atrial fibrillation: a blank period of 3 months after surgery. After 3 months of ablation surgery, atrial fibrillation/atrial flutter/atrial tachycardia with a duration of more than 30 seconds on the ECG was considered to be a recurrence of atrial fibrillation.

Inclusion Criteria: Male and non-pregnant female subjects, 18≤age≤80. Receiving or able to tolerate anticoagulant therapy. Diagnosis of atrial fibrillation using an electrocardiogram or a dynamic electrocardiogram The longest duration of atrial fibrillation episode is less than 7 days Patient is compliant and willing to complete clinical follow-up. Exclusion Criteria: Patients who have previously undergone catheter ablation of atrial fibrillation; Left ventricular ejection fraction <35%; Pregnancy, planned pregnancy or lactating women; Left atrial appendage thrombosis was detected by transesophageal ultrasound or intracardiac ultrasound; Abnormal blood system or liver and kidney function; Combined with severe organic heart disease (including congenital heart disease, valvular heart disease, dilated cardiomyopathy, hypertrophic cardiomyopathy, and patients with myocardial infarction or coronary artery bypass grafting); Patients who are considered unsuitable for inclusion by the investigator.

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