Inhaled Hydrogen Therapy's Effect on Early Recurrences of Atrial Fibrillation Post-ablation.
Atrial Fibrillation Ablation
What this study involves
The registry does not currently label this study as recruiting. Ask about its status before planning a screening visit.
- Study type
- Interventional
- Phase
- Phase 2
- Age range
- 18 years - 80 years
- Sex eligible
- All sexes
- Healthy volunteers
- Not accepted
- Participants
- 124 Estimated
These are starting points, not an eligibility decision. The research team must review the full requirements.
About the research
The goal of this clinical trial is to testing the perioperative inhaled hydrogen (H2) administration's effects during atrial fibrillation ablations (AF) to reduce both early and late recurrences associated with this procedure.
Researchers will compare H2 inhalation to the standard of care to see if we observe a reduction in AF recurrence after ablation but also a reduction in rehospitalizations or emergency visits for cardioversion, and consequently an improvement in quality of life.
Participants will:
- have an AF ablation associated to an hydrogen therapy or standard of care
- complete quality of life questionnaires
- record ECG on KardiaMobile©
- Keep a diary of their symptoms
- have a blood test
- have 2 follow-up visits (after 3 and 12 months) and 2 phone calls (after 6 and 9 months)
Who may be able to participate?
The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.
Inclusion Criteria:
1. Be over 18 years old
2. Present with paroxysmal or persistent Atrial Fibrilation (AF) of less than 6 months with symptoms
3. Be a candidate for a first-time AF ablation (cryoablation and electroporation)
4. Understand and agree to comply with the study procedures
5. Patient must have a smartphone
6. Be enrolled in a social security scheme, or have equivalent rights
7. Have signed the study consent form
Exclusion Criteria:
1. Being over 80 years old
2. Having a left atrial diameter ≥ 50mm on transthoracic echocardiography
3. Radiofrequency ablation
4. Having a history of AF ablation
5. Patient on long-term anti-inflammatory treatment
6. Patient with gas administration equipment (CPAP, NIV…)
7. Woman of childbearing potential\*
8. Non-cooperative patient
9. In the exclusion period for another study
10. Persons covered by Articles L1121-5 to L1121-8 of the Public Health Code and Articles 31 to 35 of Regulation 536/2014 (corresponding to all protected persons: pregnant women, women in labor, breastfeeding mothers, persons deprived of liberty by judicial or administrative decision, persons receiving psychiatric care under Articles L. 3212-1 and L. 3213-1 who are not covered by the provisions of Article L. 1121-8, persons admitted to a healthcare or social facility for purposes other than research, minors, persons subject to legal protection measures or unable to give their consent).
11. Staff with a hierarchical relationship with the principal investigator
Treatment, groups and participation
The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.
- Assignment
- Random assignment
- Masking
- No masking
Standard of care
patients treated with usual care (Standard of Care)
H2
patient treated with inhaled hydrogen therapy during the perioperative period
Drug: Hydrogen Gas (H2)
Hydrogen Gas (H2) DRUG
Patients treated with inhaled hydrogen therapy in the perioperative period (initiation of inhaled hydrogen therapy from hospital admission until discharge, except in the operating room) (dosage : H2/N2 3.6%/96.4%, 1 L/min 24 hours a day)
What researchers are measuring
Outcome measures describe what is being studied. They are not proof that a treatment works.
Primary measures
Effectiveness of inhaled hydrogen therapy on early recurrences of atrial fibrillation post-ablation and on the improvement of quality of life at 3 months
Time frame: From baseline (before ablation) to 3 months after ablation
Composite binary endpoint, reported as the number of participants meeting both criteria: (1) no early recurrence during the blanking period (first 3 months after ablation), where recurrence is defined as any episode of atrial fibrillation, atrial flutter or atrial tachycardia lasting at least 30 seconds; AND (2) improvement in quality of life, defined as an improvement in quality of life, defined as an increase of at least 5 points in the AFEQT overall score (range 0-100; higher scores indicate better quality of life) between baseline and 3 months.
Secondary measures
Number of hospitalizations or electrical cardioversions or pharmacological cardioversions during the blanking period (3 months)
Time frame: From ablation to 3 months after ablation
Total number of hospitalizations or electrical cardioversions or pharmacological cardioversions occurring during the blanking period, i.e. the first 3 months after ablation. The three event types are summed into a single count per participant.
Incidence of Late Atrial Fibrillation, Atrial Flutter or Atrial Tachycardia Recurrence Between 3 and 12 Months After Ablation
Time frame: From 3 months to 12 months after ablation
Number of participants with late recurrence, defined as any episode of atrial fibrillation, atrial flutter or atrial tachycardia lasting at least 30 seconds on Holter or Kardia recording, or recorded on a 12-lead electrocardiogram, occurring more than 3 months and up to 12 months after ablation.
Change in White Blood Cell Count (WBC) from before ablation to 24 and 48 hours after ablation
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Change in blood white blood cell (WBC) count, measured in 10\^9 cells/L, between 24 hours before ablation and 24 hours and 48 hours after ablation.
Change in High-Sensitivity C-Reactive Protein (CRP) from before ablation to 24 and 48 hours after Ablation
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Change in blood high-sensitivity C-reactive protein (hs-CRP) concentration, measured in mg/L, between 24 hours before ablation and 24 hours and 48 hours after ablation.
Change in Interleukin-6 from before ablation to 24 and 48 hours after Ablation
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Change in blood interleukin-6 (IL-6) concentration, measured in pg/mL, between 24 hours before ablation and 24 hours and 48 hours after ablation.
Incidence of Adverse Events Graded by NCI-CTCAE Version 5.0 (Safety and Tolerability)
Time frame: From the start of inhaled hydrogen therapy to 12 months after ablation
Number of participants with adverse events, described and graded using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0. Grades range from 1 (mild) to 5 (death related to adverse event); higher grades indicate more severe events.
Evaluate the acceptability of hydrogen therapy treatment by healthcare providers
Time frame: Day 2 after ablation
Custom hetero-questionnaire on the acceptability of hydrogen therapy treatment by healthcare providers
Review the complete result tables and limitations in the official record.
Open official results ↗Research locations (2)
The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.
2 locations
Chu Grenoble AlpesGrenoble, Isère, FranceStatus unknown
Hopital Louis PradelBron, Rhone, FranceStatus unknown
Study team and timeline
- Lead sponsor
- University Hospital, Grenoble
- Study start
- 2027-01 Estimated
- Primary completion
- 2029-01 Estimated
- Study completion
- 2029-09 Estimated
- First posted
- Nov 10, 2026 Actual
- Last updated
- Nov 10, 2026 Actual
Official study contacts
Official study title
Inhaled Hydrogen Therapy's Effect on Early Recurrences of Atrial Fibrillation Post-ablation. Phase II, Multicenter, Randomized, Controlled, Open-label Clinical Trial
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Source: ClinicalTrials.gov API v2. Information is submitted by sponsors and investigators. NLM does not approve the safety or science of all listed studies. Registry disclaimer.
Retrieved: Nov 12, 2026 · Last registry update: Nov 10, 2026