Unintended Right Atrial Lesions After Monopolar Biphasic Lattice-tip Pulsed-Field Ablation: A Case Series

Structured Abstract Background Monopolar biphasic pulsed-field ablation (PFA) delivered by a lattice-tip catheter may create deeper lesions than conventional bipolar systems. The impact on adjacent right atrial structures remains poorly characterized. Case summary We report four patients undergoing pulmonary vein isolation using a lattice-tip PFA catheter. Post-procedural electroanatomic mapping revealed unintended right atrial lesions involving the posterior right atrium, interatrial septum, or superior vena cava. In patients with short anatomical distances between right pulmonary veins and adjacent right atrial structures, lesions developed despite apparently successful pulmonary vein isolation. Catheter instability related to coughing under deep sedation appeared to contribute to broader lesion formation in two cases. Conclusion These cases suggest that monopolar biphasic lattice-tip PFA may create unintended lesions in adjacent right atrial tissue when anatomical proximity is short or catheter stability is compromised. Awareness of these mechanisms may help optimize procedural safety and lesion delivery.