Pulsed Field Ablation of SVC and PV in Paroxysmal Atrial Fibrillation (PASPA Study)

The PASPA study addresses the limitations of traditional pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF), where recurrence rates remain significant due to non-pulmonary vein triggers such as the superior vena cava (SVC). Traditional ablation near the SVC carries risks of phrenic nerve and sinus node injury, and acute isolation success rates are only 75%-85%. Pulsed Field Ablation (PFA) selectively ablates cardiomyocytes through irreversible electroporation while sparing adjacent nerves and vessels, allowing safer SVC isolation. This prospective, multicenter, randomized controlled trial will enroll 650 patients with documented PAF, randomly assigned to PVI alone or PVI plus SVC isolation (SVCI) using PFA. Participants will be followed for 12 months with 7-day Holter monitoring at 3, 6, and 12 months. The primary endpoint is freedom from atrial fibrillation, atrial flutter, or atrial tachycardia episodes ≥30 seconds at 12 months. Secondary endpoints include atrial fibrillation burden and procedure-related complications such as phrenic nerve injury, cardiac tamponade, and sinus node dysfunction. Preliminary animal and pilot human studies indicate that PFA achieves 100% acute SVC isolation with minimal complications. The study aims to determine whether adding SVCI to PVI improves efficacy in PAF without increasing procedural risks, providing evidence to guide standardized ablation strategies.

Inclusion criteria

• Documented paroxysmal AF (episodes self-terminating within 7 days), evidenced by ECG, Holter, or event monitor
• Age between 18 and 80 years
• Willing and able to provide written informed consent

Exclusion criteria

• Intracardiac thrombus (left atrium or left atrial appendage)
• Left atrial anterior-posterior diameter > 60 mm
• Absolute contraindication to anticoagulation therapy
• Stroke or myocardial infarction within 1 month prior to enrollment
• Uncontrolled hyperthyroidism
• Pregnancy or planning pregnancy
• Life expectancy less than 1 year
• Previous atrial fibrillation ablation procedure
• Known or suspected AF triggers primarily originating from the SVC (based on pre-procedure mapping, if available)
• Inability or unwillingness to participate in the study or comply with follow-up requirements