Interest of Cardiac Coherence in the Prevention of Chronic Post-traumatic Stress Disorder: Pilot Study

This pilot study is exploring whether cardiac coherence (a breathing technique that calms the nervous system) can help prevent post-traumatic stress disorder (PTSD) from developing in people who have recently experienced a traumatic event. **You may be eligible if...** - You were seen at a medico-psychological emergency unit - You have been diagnosed with acute stress disorder (based on DSM-5 criteria) - You experienced a traumatic event (as a victim or witness) in the past 3 to 15 days - You can read and write in French - You have social security coverage **You may NOT be eligible if...** - You have a respiratory condition that prevents you from doing breathing exercises - You are pregnant - You have another condition that would interfere with the study Talk to your doctor to see if this trial is right for you.