Ablation of Arrhythmia'sMICROPFANCT07610018
Cerebral Microembolization During Pulmonary Vein Isolation: Comparison of Different Pulsed Field Ablation Systems
A study testing Pulsed field ablation using PulseSelect system, Pulsed field ablation using Varipulse system and Pulsed field ablation using Farapulse system in people with Ablation of Arrhythmia's, run by Ivan Zeljkovic at 2 sites in Croatia.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Ablation of Arrhythmia's
- What is being tested?
- Pulsed field ablation using PulseSelect system, Pulsed field ablation using Varipulse system and Pulsed field ablation using Farapulse system
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 2 sitesCroatia
- Study dates
- 1 Jun 2026to 20 Jan 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18 years or older
- Paroxysmal or persistent atrial fibrillation
- Indication for catheter ablation with pulmonary vein isolation
- Feasibility of transcranial Doppler assessment
- Signed informed consent
Who cannot join
- Recent stroke or transient ischemic attack
- Significant cerebrovascular disease preventing reliable transcranial Doppler assessment
- Severe valvular or structural heart disease
- Pregnancy or breastfeeding
- Inability to receive anticoagulation
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Croatia2 sites
UH Dubrava
Zagreb, 10000
Ivan Zeljković, MD, Phd
Mihovil Santini, MD
University Hospital Center Sisters of Charity, Zagreb, Croatia
Zagreb, 10000
About this study
Official title: Cerebral Microembolization During Pulmonary Vein Isolation: a Randomized Comparison of Different Pulsed Field Ablation Systems
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.
Read the detailed description
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.
- Conditions
- Ablation of Arrhythmia's
- Being tested
- Pulsed field ablation using PulseSelect system, Pulsed field ablation using Varipulse system, Pulsed field ablation using Farapulse system, Pulsed field ablation using Sphere-9 system, Pulsed field ablation using Sphere-360 system
- Keywords
- Atrial fibrillation, Pulmonary vein isolation, Cerebral microembolization, Pulsed field ablation
- Medical subject headings
- Atrial Fibrillation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Pulsed field ablation using PulseSelect systemDevice
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.
Pulsed field ablation using Varipulse systemDevice
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.
Pulsed field ablation using Farapulse systemDevice
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
Pulsed field ablation using Sphere-9 systemDevice
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.
Pulsed field ablation using Sphere-360 systemDevice
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
| Study group | Role | What they receive |
|---|---|---|
| PulseSelect PFA | Active comparator | 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. Receives: Device: Pulsed field ablation using PulseSelect system |
| Varipulse PFA | Active comparator | 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. Receives: Device: Pulsed field ablation using Varipulse system |
| Farapulse PFA | Active comparator | 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. Receives: Device: Pulsed field ablation using Farapulse system |
| Sphere-9 PFA | Active comparator | 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. Receives: Device: Pulsed field ablation using Sphere-9 system |
| Sphere-360 PFA | Active comparator | 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 Receives: Device: Pulsed field ablation using Sphere-360 system |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: During procedure
Secondary outcomes (5)
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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: During procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 May 2026
- Study start1 Jun 2026 (estimated)
- Primary completion1 Jan 2027 (estimated)
- Study completion20 Jan 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ablation of Arrhythmia'sStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Ivan Zeljkovic
- Sponsor type
- University, hospital or other
- Collaborators
- University Hospital Dubrava, University Hospital Center Sisters of Charity, Zagreb, Croatia
- Responsible party
- Sponsor-investigator, Ivan Zeljkovic, University Hospital Dubrava
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07610018
- Sponsor's protocol ID
- 2026/0423-11
- Acronym
- MICROPFA
- Status last verified
- May 2026
- First submitted
- 14 May 2026
- Last updated
- 27 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 27 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Cerebral Microembolization During Pulmonary Vein Isolation: a Randomized Comparison of Different Pulsed Field Ablation Systems
- ClinicalTrials.gov ID
- NCT07610018
- Acronym / sponsor ID
- MICROPFA / 2026/0423-11
- Conditions
- Ablation of Arrhythmia's
- Keywords
- Atrial fibrillation, Pulmonary vein isolation, Cerebral microembolization, Pulsed field ablation
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Ivan ZeljkovicUniversity, hospital or other
- Collaborators
- University Hospital Dubrava, University Hospital Center Sisters of Charity, Zagreb, Croatia
- Study start
- 1 Jun 2026 (estimated)
- Primary completion
- 1 Jan 2027 (estimated)
- Study completion
- 20 Jan 2027 (estimated)
- First posted
- 27 May 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 5
| Arm | Type | Receives |
|---|---|---|
| PulseSelect PFA | Active comparator | Device: Pulsed field ablation using PulseSelect systemParticipants 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. |
| Varipulse PFA | Active comparator | Device: Pulsed field ablation using Varipulse systemParticipants 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. |
| Farapulse PFA | Active comparator | Device: Pulsed field ablation using Farapulse systemParticipants 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. |
| Sphere-9 PFA | Active comparator | Device: Pulsed field ablation using Sphere-9 systemParticipants 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. |
| Sphere-360 PFA | Active comparator | Device: Pulsed field ablation using Sphere-360 systemParticipants 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 |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Age 18 years or older
- Paroxysmal or persistent atrial fibrillation
- Indication for catheter ablation with pulmonary vein isolation
- Feasibility of transcranial Doppler assessment
- Signed informed consent
Key exclusion criteria (5 listed)
- Recent stroke or transient ischemic attack
- Significant cerebrovascular disease preventing reliable transcranial Doppler assessment
- Severe valvular or structural heart disease
- Pregnancy or breastfeeding
- Inability to receive anticoagulation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Pulsed field ablation using PulseSelect systemPulmonary 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. | Device | PulseSelect PFA |
| Pulsed field ablation using Varipulse systemPulmonary 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. | Device | Varipulse PFA |
| Pulsed field ablation using Farapulse systemPulmonary 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 | Device | Farapulse PFA |
| Pulsed field ablation using Sphere-9 systemPulmonary 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. | Device | Sphere-9 PFA |
| Pulsed field ablation using Sphere-360 systemPulmonary 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 | Device | Sphere-360 PFA |
Primary outcome
Change in microembolic signal burden after pulmonary vein isolation
Time frame: During procedure
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.
5 secondary outcomes
Within-group change in microembolic signal burden
Time frame: During procedure
Incidence of new microembolic signals after ablation
Time frame: Immediately after the ablation procedure
Procedure-related clinical neurological events
Time frame: From the start of the ablation procedure through 72 hours after the procedure
Association between procedure duration and ΔMES
Time frame: During procedure
Association between number of ablation applications and ΔMES
Time frame: During procedure
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 May 2026.
- Individual participant dataSharing planned: Undecided
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Pulsed field ablation using PulseSelect system, Pulsed field ablation using Varipulse system and Pulsed field ablation using Farapulse system in people with Ablation of Arrhythmia's, run by Ivan Zeljkovic at 2 sites in Croatia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 27 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Croatia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ivan Zeljković, PhD,MD (+385917823289, ivanzeljkov@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in microembolic signal burden after pulmonary vein isolation (time frame: During procedure). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 May 2026.