This study is a prospective, single-center, single-arm, non-randomized study focused on safety and preliminary efficacy, aiming to evaluate the safety and preliminary efficacy of a cardiac pulsed field ablation device and a single-use cardiac surgical pulsed field ablation electrode for elective cardiovascular surgery combined with Cox-maze IV surgery as a reference treatment for atrial fibrillation. Adult subjects meeting the clinical indications for concomitant cardiac surgery will undergo the Cox-maze IV procedure as a reference, which includes isolation of the left and right pulmonary veins and a series of ablation lines to create a box isolation area on the posterior free wall of the left atrium, as well as linear ablation on the mitral annulus and left atrial appendage. On the right side of the heart, ablation will be performed on the anterior free wall of the right atrium, right atrial appendage, and from the right atrial appendage to the tricuspid annulus, with immediate verification of effective pulmonary vein isolation. After the completion of surgical ablation, all subjects will be followed up in the hospital before discharge, and at 30±7 days, 90±14 days, and 180±30 days postoperatively. The blanking period refers to a specified 90-day observation period after surgery during which events are not included in the secondary efficacy evaluation. All subjects will undergo assessment based on electrocardiographic records at 180 days following surgical ablation to evaluate the success of the procedure.

Inclusion Criteria:

• Subjects aged ≥ 18 years and ≤ 80 years;
• Subjects are willing and able to sign the informed consent form to receive study treatment, including surgical atrial fibrillation ablation, and complete the follow-up specified in the clinical study protocol;
• Subjects with a history, electrocardiogram, or Holter ECG confirming paroxysmal atrial fibrillation, persistent atrial fibrillation (lasting more than seven days, or less than seven days but requiring drug or electrical cardioversion), or long-standing persistent atrial fibrillation (lasting more than one year);
• Left ventricular ejection fraction > 30% (determined by echocardiography or cardiac catheterization within 60 days prior to enrollment, as recorded in the patient's medical history);
• Subjects scheduled to undergo open-heart surgery, including one or more of the following cardiac surgeries performed under direct vision: mitral valve repair or replacement, aortic valve repair or replacement, tricuspid valve repair or replacement, and coronary artery bypass grafting;
• Subjects with an expected survival of ≥ 1 year.

Exclusion Criteria:

• Subjects with implanted electronic medical devices (such as pacemakers, ICDs, or CRT) or left atrial appendage devices;
• Subjects with artificial heart valves;
• Subjects with atrial fibrillation only, without indications for coronary artery bypass grafting (CABG) and/or valve surgery;
• History of previous atrial fibrillation ablation, atrioventricular (AV) node ablation, or Maze procedure;
• History of previous cardiac surgery (reoperation);
• Wolff-Parkinson-White (WPW) syndrome or other supraventricular arrhythmias, AV nodal reentry, ventricular arrhythmias requiring antiarrhythmic drug treatment, or uncontrolled bradyarrhythmias (sinus bradycardia, junctional rhythm, ventricular escape rhythm, sinus arrest, sinoatrial block, second-degree AV block, third-degree AV block, and sick sinus syndrome).