A Phase 2 interventional study of Hydrogen Gas (H2) in Atrial Fibrillation Ablation, sponsored by University Hospital, Grenoble. Not yet recruiting at 2 sites in France. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by University Hospital, Grenoble · Phase 2, Interventional, and Prevention
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:
4,009 studies on the registry are indexed under Atrial Fibrillation; 961 are open to participants now.
This study's planned enrollment of 124 is below the median of 150 across 2,476 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →University Hospital, Grenoble is the lead sponsor of 837 studies on the registry; 207 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
patients treated with usual care (Standard of Care)
patient treated with inhaled hydrogen therapy during the perioperative period
Drug: Hydrogen Gas (H2)
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)
Also known as: inhaled hydrogen therapy
Effectiveness of inhaled hydrogen therapy on early recurrences of atrial fibrillation post-ablation and on the improvement of quality of life at 3 months
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.
Time frame: From baseline (before ablation) to 3 months after ablation
Number of hospitalizations or electrical cardioversions or pharmacological cardioversions during the blanking period (3 months)
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.
Time frame: From ablation to 3 months after ablation
Incidence of Late Atrial Fibrillation, Atrial Flutter or Atrial Tachycardia Recurrence Between 3 and 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.
Time frame: From 3 months to 12 months after ablation
Change in White Blood Cell Count (WBC) from before ablation to 24 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.
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Change in High-Sensitivity C-Reactive Protein (CRP) from before ablation to 24 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.
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Change in Interleukin-6 from before ablation to 24 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.
Time frame: 24 hours before ablation, 24 hours after ablation, and 48 hours after ablation
Incidence of Adverse Events Graded by NCI-CTCAE Version 5.0 (Safety and Tolerability)
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.
Time frame: From the start of inhaled hydrogen therapy to 12 months after ablation
Evaluate the acceptability of hydrogen therapy treatment by healthcare providers
Custom hetero-questionnaire on the acceptability of hydrogen therapy treatment by healthcare providers
Time frame: Day 2 after ablation
Start is estimated for Jan 2027; primary completion for Jan 2029, 24 months later.
Of 41 phase 2 interventional studies under Atrial Fibrillation, half reached primary completion within 32 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 39. This study's planned 24 months is below that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Hydrogen
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