Atrial FibrillationPARALELLNCT05408754
Pulsed Field Ablation and Pulsed Field CRyoAbLation in PErsistent AtriaL FibrilLation
A study testing Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF. in people with Atrial Fibrillation, run by Adagio Medical at 6 sites in 6 countries.
Trial summary
A prospective, two-arm, multi-center, randomized, open-label, pre-market, First-in-Human clinical study designed to provide safety and performance data regarding the use of the Adagio PFA and PFCA Systems in the treatment of PsAF. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Atrial Fibrillation
- What is being tested?
- Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 89 participants
- Where
- 6 sitesin 6 countries
- Study dates
- 20 Oct 2022to 3 Mar 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- IC 1 Male or female between the ages of 18 - 80 years
- IC 2 Currently scheduled for an ablation of symptomatic persistent (> 7 days) atrial fibrillation within the past year documented by ECG or Continuous Holter monitoring
- IC 3 Refractory to at least one class I or III AAD. (Refractory defined as not effective or not tolerated)
- IC 4 Willingness, ability, and commitment to participate in baseline and follow-up evaluations for the full length of the study
- IC 5 Willingness and ability to give an informed consent
Who cannot join
- EC 1 In the opinion of the Investigator, any known contraindication to an atrial ablation, TEE, or anticoagulation. Including but not limited to the identification of any atrial thrombus or evidence of sepsis
- EC 2 Continuous AF lasting longer than 12-months
- EC 3 History of previous left atrial ablation or surgical treatment for AF/AFL/AT
- EC 4 AF secondary to electrolyte imbalance, active thyroid disease, or any other reversible or non-cardiac cause
- EC 5 Structural heart disease as described below:
- Left ventricular ejection fraction (LVEF) < 40% based on most recent TTE
Show all 30Show fewer
- Left atrial size > 55 mm (parasternal long axis view) documented within 6-months of screening
- NYHA Class III or IV heart failure documented within the previous 12-months
- An implanted pacemaker or ICD
- Previous cardiac surgery, ventriculotomy, or atriotomy (excluding atriotomy for CABG),
- Previous cardiac valvular surgical or percutaneous procedure, or prosthetic valve
- Interatrial baffle, closure device, patch, or PFO occluder
- Presence of a left atrial appendage occlusion device
- Presence of any pulmonary vein stenting devices
- Coronary artery bypass graft (CABG) or PTCA procedure within six (6) months prior to procedure
- Unstable angina or ongoing myocardial ischemia
- Myocardial infarction within the previous six (6) months prior to procedure
- Moderate or severe mitral insufficiency or stenosis based on most recent TTE
- Atrial myxoma
- Significant congenital anomaly
- EC 6 BMI > 40
- EC 7 Any previous history of cryoglobulinemia (for those patients randomized to the PFCA arm)
- EC 8 History of blood clotting or bleeding disease
- EC 9 History of severe COPD requiring steroid use in the previous 12-months
- EC 10 History of severe sleep apnea (AHI > 30) not currently treated with a CPAP machine or other mechanical device
- EC 11 Stroke or TIA within the last year.
- EC 12 Any prior history or current evidence of hemidiaphragmatic paralysis
- EC 13 Pregnant or lactating (current or anticipated during study follow-up
- EC 14 Current enrollment in any other study protocol where testing or results from that study may interfere with the procedure or outcome measurements for this study
- EC 15 Any other conditions such as, mental illness, addictive disease, terminal illness with a life expectancy of less than two years, extensive travel away from the research center that may lead to non-compliance with the protocol procedure or follow up
Trial locations and contacts
6 sites in 6 countries.
6 sites in 6 countries
Canada1 site
McGill University Health Centre (MUHC), Montreal General Hospital (MGH)
Montreal, Quebec, H3G 1A4
About this study
Official title: PARALELL - Pulsed Field Ablation and Pulsed Field CRyoAbLation in PErsistent AtriaL FibrilLation
A prospective, two-arm, multi-center, randomized, open-label, pre-market, First-in-Human clinical study designed to provide safety and performance data regarding the use of the Adagio PFA and PFCA Systems in the treatment of PsAF.
Read the detailed description
Enrolled subjects will be treated (ablation) with the Adagio PFA or PFCA System in a 1:1 randomized fashion.
Treatment will include the isolation of pulmonary veins (PVIs), and isolation of the left atrial posterior wall (PWI), and CTI at the discretion and clinical judgment of the investigator.
Data will be collected throughout 12-month follow up period to assess safety and performance of the device. Recurrence of atrial arrhythmias is measured by 12-lead ECGs and 48-hour continuous ECG recording (Holter).
- Conditions
- Atrial Fibrillation
- Being tested
- Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.
- Keywords
- Pulsed Field Ablation, Pulsed Field CryoAblation, Persistent AF, PFA, PFCA, AF, Adagio Medical
- Medical subject headings
- Atrial Fibrillation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.Device
Treatment will include the isolation of pulmonary veins (PVIs), and isolation of the left atrial posterior wall (PWI). A right atrial cavo-tricuspid line for bi-directional block may be performed at discretion and clinical judgment of the investigator
| Study group | Role | What they receive |
|---|---|---|
| Pulsed Field Ablation (PFA) group | Experimental | PsAF patients treated by PFA Receives: Device: Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF. |
| Pulsed Field CryoAblation (PFCA) group | Experimental | PsAF patients treated by PFCA Receives: Device: Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Primary Endpoint for Safety
Analysis of the proportion of subjects who are free from device/procedure-related Major Adverse Events that occur during or following the ablation procedure
Measured: Up to 7 days following the ablation procedure
Primary Procedural Performance Outcome
Analysis of the evidence of procedural electrical isolation of all pulmonary veins, posterior wall, and bidirectional block (if applicable) across all other ablation lines using the study device.
Measured: Procedure
Secondary outcomes (8)
One-Year Safety
Recording and analysis of all identified serious adverse events and serious adverse device effects through 12 months post-procedure.
Measured: 12 months
One-Year Performance
Proportion of subjects receiving a single ablation procedure who has freedom from any documented left atrial arrhythmia (AF/AFL/AT) lasting longer than 30 seconds following the Blanking Period (3-months ± 14-days post index ablation) using a continuous 48-hour ECG recording through 12 months post-procedure.
Measured: 12 months
Procedural Performance - ablation time
Ablation time defined as the total time for energy delivery to achieve PVI, PWI, and CTI (if applicable)
Measured: procedure
Procedural Performance - procedure time
Total procedure time defined as the time from first venous access to the removal of the catheters from the heart at the end of the procedure
Measured: procedure
Procedural Performance - fluoroscopy time
Procedure fluoroscopy time
Measured: procedure
Procedural Performance - intraprocedural PV reconnection rate
The rate of intraprocedural PV reconnection - defined as confirmed conduction across a PVI line during the 20-minute waiting period to confirm PVI
Measured: procedure
Procedural Performance - AAD use
Recording of the use of AADs in the follow up period beyond a 90-day blanking period
Measured: procedure and up to 12-month
Procedural Performance - repeat ablation
Number of repeat ablations within and following the blanking period
Measured: procedure and up to 12-month
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Jun 2022
- Study start20 Oct 2022
- Primary completion14 Oct 2024
- Study completion3 Mar 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Atrial FibrillationStudies 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
- 89 participants (actual)
Sponsor and investigators
- Lead sponsor
- Adagio Medical
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Atul Verma, MD, Principal investigator, McGill University Health Centre; Montreal, Canada
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05408754
- Sponsor's protocol ID
- CS-169
- Acronym
- PARALELL
- Status last verified
- Sep 2025
- First submitted
- 2 Jun 2022
- Last updated
- 13 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 13 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- PARALELL - Pulsed Field Ablation and Pulsed Field CRyoAbLation in PErsistent AtriaL FibrilLation
- ClinicalTrials.gov ID
- NCT05408754
- Acronym / sponsor ID
- PARALELL / CS-169
- Conditions
- Atrial Fibrillation
- Keywords
- Pulsed Field Ablation, Pulsed Field CryoAblation, Persistent AF, PFA, PFCA, AF, Adagio Medical
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 89 participants (actual)
- Lead sponsor
- Adagio MedicalIndustry (pharma, biotech, devices)
- Study start
- 20 Oct 2022 (actual)
- Primary completion
- 14 Oct 2024 (actual)
- Study completion
- 3 Mar 2025 (actual)
- First posted
- 7 Jun 2022 (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.
A prospective, two-arm, multi-center, randomized, open-label, pre-market, First-in-Human clinical study designed to provide safety and performance data regarding the use of the Adagio PFA and PFCA Systems in the treatment of PsAF.
Detailed description
Enrolled subjects will be treated (ablation) with the Adagio PFA or PFCA System in a 1:1 randomized fashion.
Treatment will include the isolation of pulmonary veins (PVIs), and isolation of the left atrial posterior wall (PWI), and CTI at the discretion and clinical judgment of the investigator.
Data will be collected throughout 12-month follow up period to assess safety and performance of the device. Recurrence of atrial arrhythmias is measured by 12-lead ECGs and 48-hour continuous ECG recording (Holter).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Pulsed Field Ablation (PFA) group | Experimental | Device: Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.PsAF patients treated by PFA |
| Pulsed Field CryoAblation (PFCA) group | Experimental | Device: Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.PsAF patients treated by PFCA |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- IC 1 Male or female between the ages of 18 - 80 years
- IC 2 Currently scheduled for an ablation of symptomatic persistent (> 7 days) atrial fibrillation within the past year documented by ECG or Continuous Holter monitoring
- IC 3 Refractory to at least one class I or III AAD. (Refractory defined as not effective or not tolerated)
- IC 4 Willingness, ability, and commitment to participate in baseline and follow-up evaluations for the full length of the study
- IC 5 Willingness and ability to give an informed consent
Key exclusion criteria (30 listed)
- EC 1 In the opinion of the Investigator, any known contraindication to an atrial ablation, TEE, or anticoagulation. Including but not limited to the identification of any atrial thrombus or evidence of sepsis
- EC 2 Continuous AF lasting longer than 12-months
- EC 3 History of previous left atrial ablation or surgical treatment for AF/AFL/AT
- EC 4 AF secondary to electrolyte imbalance, active thyroid disease, or any other reversible or non-cardiac cause
- Left ventricular ejection fraction (LVEF) < 40% based on most recent TTE
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 |
|---|---|---|
| Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF.Treatment will include the isolation of pulmonary veins (PVIs), and isolation of the left atrial posterior wall (PWI). A right atrial cavo-tricuspid line for bi-directional block may be performed at discretion and clinical judgment of the investigator | Device | Pulsed Field Ablation (PFA) group, Pulsed Field CryoAblation (PFCA) group |
Primary outcome
Primary Endpoint for Safety
Time frame: Up to 7 days following the ablation procedure
Analysis of the proportion of subjects who are free from device/procedure-related Major Adverse Events that occur during or following the ablation procedure
Primary Procedural Performance Outcome
Time frame: Procedure
Analysis of the evidence of procedural electrical isolation of all pulmonary veins, posterior wall, and bidirectional block (if applicable) across all other ablation lines using the study device.
8 secondary outcomes
One-Year Safety
Time frame: 12 months
One-Year Performance
Time frame: 12 months
Procedural Performance - ablation time
Time frame: procedure
Procedural Performance - procedure time
Time frame: procedure
Procedural Performance - fluoroscopy time
Time frame: procedure
Procedural Performance - intraprocedural PV reconnection rate
Time frame: procedure
Procedural Performance - AAD use
Time frame: procedure and up to 12-month
Procedural Performance - repeat ablation
Time frame: procedure and up to 12-month
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Apr 2026.
- Individual participant dataSharing planned: No
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Atrial Fibrillation (AF)
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. This study is not recruiting at the moment.
Atul Verma, MD principal investigator
McGill University Health Centre; Montreal, Canada
6 sites in 6 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Atrial ablation for subject scheduled for a de novo endocardial ablation of symptomatic, drug-refractory PsAF. in people with Atrial Fibrillation, run by Adagio Medical at 6 sites in 6 countries.
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 30 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: finished, as of the sponsor's last update on 13 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in Belgium, Canada, Czechia, Ireland, Netherlands and 1 more country. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Primary Endpoint for Safety (time frame: Up to 7 days following the ablation procedure). The study lists 2 primary outcomes in all. 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 13 Apr 2026.