TWOSOME Trial: Single-Shot Versus Single-Tip Pulsed Field Ablation for Pulmonary Vein Isolation

Safety and Efficacy of New, Non-thermal Ablation Techniques for the Treatment of Atrial Fibrillation - A Comparison of Two Ablation Systems

Two non-thermal ablation techniques approved for routine clinical practice (CE-marked) for the interventional treatment of atrial fibrillation are compared in a 1:1 randomization to investigate patient data, procedural data, effectiveness, and safety.

Patients with paroxysmal atrial fibrillation were randomized 1:1 to undergo pulmonary vein isolation using pulsed field ablation (PFA) with either single-shot PFA (FARAPULSE) or single-tip PFA (Galvanize Therapeutics). Baseline characteristics, procedural data, effectiveness, and safety outcomes were analyzed. In each group, a subset of consecutive patients underwent cerebral magnetic resonance imaging to assess silent cerebral lesions and was scheduled for biomarker assessment (blood sampling) to evaluate inflammation and troponin release after PFA.

Inclusion Criteria:

• Recurrent, symptomatic paroxysmal atrial fibrillation
• Age > 18 years
• Patient consen

Exclusion Criteria:

• Refusal of the patient
• Inability to provide informed consent
• Life expectancy < 2 years
• Pregnancy and breastfeeding (due to radiation exposure)
• History of left atrial ablation
• Known macro-reentry or focal atrial tachycardia
• Significant mitral valve stenosis
• History of heart valve replacement or reconstruction
• NYHA class III and IV
• Left ventricular ejection fraction < 35%
• Left atrial enlargement > 55 mm on echocardiography
• Intracardiac thrombus prior to the procedure
• Severe pulmonary disease with abnormal blood gases or requiring oxygen therapy
• Renal insufficiency (GFR < 30 mL/min) due to contrast medium use
• Stroke or TIA within the last 6 months
• Symptomatic carotid stenosis
• Active malignancy within the previous 24 months
• Untreated or uncontrolled thyroid disease
• Active bleeding or chronic bleeding tendency not amenable to curative treatment
• Body mass index > 35 kg/m²
• Contraindication to CT examination (e.g., contrast medium allergy or severe claustrophobia)