Influence of 100% oxygen inhaled under hyperbaric conditions in patients with cardiac symptoms after COVID-19 infection

INTERVENTION: Trade Name: Oxygen Product Name: Sauerstoff medicAL Product Code: V03AN01 Pharmaceutical Form: Inhalation vapour INN or Proposed INN: Oxygen CAS Number: 7782‐44‐7 Other descriptive name: OXYGEN Concentration unit: % (W/V) percent weight/volume Concentration type: not less then Concentration number: 99.5‐ CONDITION: Multiorgan symptoms after COVID‐19 infection (Long COVID) Therapeutic area: Body processes [G] ‐ Biological Phenomena [G16] PRIMARY OUTCOME: Main Objective: The aim of the current study is to investigate the feasibility, safety and success of hyperbaric oxygen therapy in patients suffering from multiorgan symptoms considering orthostatic dysregulation (postural orthostatic tachycardia) after having contracted a COVID‐19 infection (i.e."Long COVID"). Primary end point(s): Hyperbaric oxygen treatment (HBO) leads to a significant improvement of the peak oxygen consumption of more than at least 15%, improvement of the blood gas values, the vital signs, the personal oxygen demand, the personal well being and the orthostatic dysregulation in patients with Long‐COVID symptoms. Secondary Objective: not applicable. Timepoint(s) of evaluation of this end point: 1. At the start and after 4 weeks: ; ‐ Laboratory parameters (including Trop‐T, D‐Dimer, WBC, RBC, IL‐6, CRP, Ferritin, CoV‐19 antibodies); ‐ SF‐36 questionnaire, Borg dyspnea score, fatigue assessment scale and Post‐COVID‐19 Functional Status scale (PCFS); ‐ Schellong test; ‐ Bodyplethysmography; ‐ Spiroergometry; ; 2. During HBO (cross over time point); ‐ Laboratory parameters (including Trop‐T, D‐Dimer, WBC, RBC, IL‐6, CRP, Ferritin, CoV‐19 antibodies); ‐ SF‐36 questionnaire, Borg dyspnea score, fatigue assessment scale and Post‐COVID‐19 Functional Status scale (PCFS); ‐ Schellong test; ‐ Bodyplethysmography; ‐ Spiroergometry; ; 3. Regularly during HBO; ‐ Blood pressure; ‐ Heart rate; ‐ Blood gases; ‐ Need for oxygen‐supplementation; ; 4. 3 months; ‐ Questionnaires mentioned above SECONDARY OUTCOME: Secondary end point(s): Effect of HBO treatment on laboratory parameters related to inflammation and epithelial damage, tissue oxygen levels, lung function parameters, Borg dyspnea score (46), fatigue assessment scale, post‐COVID‐19 functional status scale (PCFS) and parameters from the SF‐36 questionnaire. Timepoint(s) of evaluation of this end point: 1. At the start and after 4 weeks: ; ‐ Laboratory parameters (including Trop‐T, D‐Dimer, WBC, RBC, IL‐6, CRP, Ferritin, CoV‐19 antibodies); ‐ SF‐36 questionnaire, Borg dyspnea score, fatigue assessment scale and Post‐COVID‐19 Functional Status scale (PCFS); ‐ Schellong test; ‐ Bodyplethysmography; ‐ Spiroergometry; ; 2. During HBO (cross over time point); ‐ Laboratory parameters (including Trop‐T, D‐Dimer, WBC, RBC, IL‐6, CRP, Ferritin, CoV‐19 antibodies); ‐ SF‐36 questionnaire, Borg dyspnea score, fatigue assessment scale and Post‐COVID‐19 Functional Status scale (PCFS); ‐ Schellong test; ‐ Bodyplethysmography; ‐ Spiroergometry; ; 3. Regularly during HBO; ‐ Blood pressure; ‐ Heart rate; ‐ Blood gases; ‐ Need for oxygen‐supplementation; ; 4. 3 months; ‐ Questionnaires mentioned above INCLUSION CRITERIA: 1. Age 18 ‐90 years 2. Evident COVID‐19 infection based on clinical diagnosis and at least one positive PCR test or Antibody test 3. Patients beyond 12 weeks after initial COVID‐19 diagnosis, having failed to reassume their former life because of at least two lingering symptoms such as fatigue, dizziness, muscle weakness, insomnia, joint pain, myalgia, or headache lasting at least for 12 weeks (corresponding to grade 2‐ 4 of the current post‐COVID‐19 functional status scale) 4. Patients wit orthostatic dysregulation (postural orthostatic tachycardia) in Long‐ COVID 5. No active COVID‐19 disease (as documented by negative PCR‐test prior to enrolment). 6. Subject willing and able to read, understand and sign an informed consent and to do self‐reporting according to questionnaire. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range