An interventional study of Pulsed field ablation using PulseSelect system and Pulsed field ablation using Varipulse system in Ablation of Arrhythmia's, sponsored by Ivan Zeljkovic. Not yet recruiting at 2 sites in Croatia. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-27.
Sponsored by Ivan Zeljkovic · Not applicable, Interventional, and Treatment
This prospective, randomized, parallel-group interventional study will compare cerebral microembolization during pulmonary vein isolation between different pulsed field ablation systems in patients with paroxysmal or persistent atrial fibrillation. Adult patients with an indication for catheter ablation will be randomized to one of the included ablation systems: PulseSelect, Varipulse, Farapulse, Sphere-9, or Sphere-360. Microembolic signals will be assessed using transcranial Doppler before and after the procedure. The primary outcome will be the difference in the change in microembolic signal burden, expressed as ΔMES, between the different ablation systems.
This study is designed as a prospective, randomized, parallel-group interventional trial conducted at Clinical Hospital Dubrava, Zagreb, Croatia and University Hospital Center Sisters of Charity, Zagreb, Croatia. The study will include adult patients with paroxysmal or persistent atrial fibrillation who have a clinical indication for catheter ablation with pulmonary vein isolation.
Eligible patients will be randomized using a computer-generated randomization sequence to undergo pulmonary vein isolation with one of the following pulsed field ablation systems: PulseSelect, Varipulse, Farapulse, Sphere-9, or Sphere-360. All procedures will be performed according to standard clinical practice, with continuous periprocedural anticoagulation in accordance with current guidelines.
Cerebral microembolization will be assessed using transcranial Doppler. The examination will be performed immediately before the ablation procedure and repeated after the procedure. The presence and number of microembolic signals will be recorded. This will allow assessment of changes in microembolic signal burden within each group and comparison of these changes between different pulsed field ablation systems.
Demographic, clinical, and procedural data will be collected, including age, sex, type of atrial fibrillation, comorbidities, procedure duration, number of ablation applications, and procedural complications. The study will also record procedure-related clinical neurological events.
The primary outcome will be the difference in the change in the number of microembolic signals before and after the procedure, expressed as ΔMES, between the different pulsed field ablation systems. Secondary outcomes will include within-group changes in microembolic signal burden, incidence of new microembolic signals after the procedure, association between procedural parameters and ΔMES, and occurrence of procedure-related neurological events.
3,870 studies on the registry are indexed under Atrial Fibrillation; 924 are open to participants now.
This study's planned enrollment of 100 is below the median of 144 across 2,380 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →Ivan Zeljkovic is the lead sponsor of 3 studies on the registry; 3 are open to participants now.
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Exclusion Criteria:
Participants randomized to this arm will undergo clinically indicated pulmonary vein isolation using the PulseSelect pulsed field ablation system. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Device: Pulsed field ablation using PulseSelect system
Participants randomized to this arm will undergo clinically indicated pulmonary vein isolation using the Varipulse pulsed field ablation system. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Device: Pulsed field ablation using Varipulse system
Participants randomized to this arm will undergo clinically indicated pulmonary vein isolation using the Farapulse pulsed field ablation system. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Device: Pulsed field ablation using Farapulse system
Participants randomized to this arm will undergo clinically indicated pulmonary vein isolation using the Sphere-9 pulsed field ablation system. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Device: Pulsed field ablation using Sphere-9 system
Participants randomized to this arm will undergo clinically indicated pulmonary vein isolation using the Sphere-360 pulsed field ablation system. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure
Device: Pulsed field ablation using Sphere-360 system
Pulmonary vein isolation will be performed using the PulseSelect pulsed field ablation system in patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Pulmonary vein isolation will be performed using the Varipulse pulsed field ablation system in patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Pulmonary vein isolation will be performed using the Farapulse pulsed field ablation system in patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedu
Pulmonary vein isolation will be performed using the Sphere-9 pulsed field ablation system in patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure.
Pulmonary vein isolation will be performed using the Sphere-360 pulsed field ablation system in patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Cerebral microembolic signals will be assessed by transcranial Doppler before and after the procedure
Change in microembolic signal burden after pulmonary vein isolation
Difference in the number of cerebral microembolic signals detected by transcranial Doppler before and after pulmonary vein isolation, expressed as ΔMES, compared between the different pulsed field ablation systems.
Time frame: During procedure
Within-group change in microembolic signal burden
Change in the number of cerebral microembolic signals detected by transcranial Doppler before and after pulmonary vein isolation within each pulsed field ablation system group.
Time frame: During procedure
Incidence of new microembolic signals after ablation
Proportion of participants with newly detected cerebral microembolic signals on transcranial Doppler after pulmonary vein isolation.
Time frame: Immediately after the ablation procedure
Procedure-related clinical neurological events
Occurrence of clinically evident neurological events related to the ablation procedure, including stroke or transient ischemic attack.
Time frame: From the start of the ablation procedure through 72 hours after the procedure
Association between procedure duration and ΔMES
Association between total procedure duration and the change in cerebral microembolic signal burden before and after pulmonary vein isolation.
Time frame: During procedure
Association between number of ablation applications and ΔMES
Association between the number of pulsed field ablation applications delivered during pulmonary vein isolation and the change in cerebral microembolic signal burden before and after the procedure.
Time frame: During procedure
Plan to share: Undecided
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Ivan Zeljkovic