Peri-procedural Hydration to Prevent Acute Kidney Injury After Pulsed Field Ablation for Atrial Fibrillation

Inclusion Criteria: Participants must meet all of the following criteria: * Age ≥18 years. * Symptomatic paroxysmal atrial fibrillation (AF) or persistent AF: 1. Paroxysmal AF: AF that terminates spontaneously or with intervention within 7 days of onset, and meets both of the following: 1. At least 2 symptomatic paroxysmal AF episodes within 6 months before enrollment; 2. At least 1 documented AF episode by electrocardiogram (ECG) or Holter monitoring within 12 months before enrollment. 2. Persistent AF: AF lasting \>7 days and ≤365 days, and meets both of the following: 1. At least 1 symptomatic persistent AF episode within 6 months before enrollment; 2. Persistent AF documented within 12 months before enrollment by either Holter monitoring or 2 ECGs obtained at least 7 days apart. * Failure of antiarrhythmic drug (AAD) therapy, defined as inadequate efficacy and/or intolerance to at least 1 Class I or Class III AAD. * Planned to undergo pulsed field ablation (PFA). * Willing and able to provide written informed consent. * Willing and able to comply with study procedures, including in-hospital assessments and 30-day and 90-day follow-up. Exclusion Criteria: Participants meeting any of the following criteria will be excluded: * AF due to a reversible cause, such as hyperthyroidism or perioperative/cardiothoracic surgery-related AF. * No oral anticoagulation for at least 3 weeks before ablation. * Intracardiac thrombus. * Contraindication to anticoagulant therapy or iodinated contrast media. * Significant valvular heart disease, including moderate or severe aortic stenosis, severe aortic regurgitation, moderate or severe mitral stenosis, or severe mitral regurgitation. * Myocardial infarction within 3 months before enrollment. * Cardiac surgery within 3 months before enrollment. * New York Heart Association (NYHA) class III or IV congestive heart failure. * Left ventricular ejection fraction (LVEF) \<35%. * Hypertrophic cardiomyopathy. * Severe liver disease (Child-Pugh score \>7). * Stage 4 or 5 chronic kidney disease (eGFR \<30 mL/min/1.73 m²). * History of kidney transplantation. * Need for renal replacement therapy (RRT) at enrollment or any history of prior RRT. * Intravascular iodinated contrast administration within 7 days before enrollment. * Active systemic infection. * Known pregnancy or breastfeeding. * Participation in another clinical trial that may affect the results of this study. * Unwillingness or inability to comply with study procedures and follow-up, including participants considered by the investigator to be at substantial risk for poor adherence.