Non-invasive MSOT Examination of Muscle Oxygenation in Athletes and PAD Patients

NCT07347535 | Not Yet Recruiting

• 1 other identifier: MSOT_SPO2RT
• Study Type: observational
• Target: 60
• Locations: 0 countries
• Sites: N/A

Brief Summary

The aim of the study is to present the quantitative differences in oxygenated hemoglobin in different cohorts. This clinical study evaluates whether there is a correlation between measurements using multispectral optoacoustic tomography and the results of spiroergometry in the context of performance diagnostics.

Conditions

PAD - Peripheral Arterial Disease

Keywords

MSOT; PAD; Spiroergometry

Outcome Measures

Primary Outcomes (11)

• Hemoglobin associated parameters measured via Multispectral optoacoustic Tomography

  using MSOT

  through study completion, an average of 1 year

• Peak oxygen uptake (VO₂peak): VO₂peak (mL·kg-¹·min-¹)

  Peak oxygen uptake measured during cardiopulmonary exercise testing (CPET), defined as the highest oxygen uptake achieved during maximal exercise.

  through study completion, an average of 1 year

• Respiratory exchange ratio (RER): RER (VCO₂/VO₂, unitless)

  Respiratory exchange ratio measured during cardiopulmonary exercise testing (CPET) and calculated as the ratio of carbon dioxide production to oxygen consumption (VCO₂/VO₂).

  Through study completion, average of 1 year

• Minute ventilation: Ventilation (L·min-¹)

  Minute ventilation measured during cardiopulmonary exercise testing (CPET).

  Through study completion, average of 1 year

• Carbon dioxide production (VCO₂): VCO₂ (mL·min-¹)

  Carbon dioxide production measured during cardiopulmonary exercise testing (CPET).

  Through study completion, average of 1 year

• Heart rate response to exercise: Heart rate (bpm)

  Heart rate measured at peak exercise during cardiopulmonary exercise testing (CPET).

  Through study completion, average of 1 year

• Absolute oxygen consumption: VO₂ (mL·min-¹)

  Oxygen consumption measured during cardiopulmonary exercise testing (CPET).

  Through study completion, average of 1 year

• Anaerobic threshold: HR or workload at AT unit: bpm or km/h

  Heart rate and workload at anaerobic threshold determined during cardiopulmonary exercise testing (CPET).

  Through study completion, average of 1 year

• Breathing reserve; Percentage (%)

  using CPET Breathing reserve measured during cardiopulmonary exercise testing (CPET) and calculated as the percentage difference between maximal voluntary ventilation and peak exercise ventilation.

  Through study completion (an average of 1 year)

• Ventilatory equivalent for oxygen (VE/VO₂): Unitless

  Ventilatory equivalent for oxygen measured during cardiopulmonary exercise testing (CPET) and defined as the ratio of minute ventilation to oxygen consumption.

  Through study completion (an average of 1 year)

• Ventilatory equivalent for carbon dioxide (VE/VCO₂): Unitless

  Ventilatory equivalent for carbon dioxide measured during cardiopulmonary exercise testing (CPET) and defined as the ratio of minute ventilation to carbon dioxide production.

  Through study completion (an average of 1 year)

Study Arms (6)

PAD - peripheral artery disease

Patients with PAD

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

Triathletes

very fit subjects, who do triathlon

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

Strength athletes

Strength athletes and bodybuilders

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

young, unathletic group

Young, healthy and unathletic subjects between 18 - 40 years

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

older, unathletic group

older, unathletic and healthy subjects between 55 - 75 years

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

training PAD Patients

Diagnostic Test: MSOT - Multispectral optoacustic tomography; Diagnostic Test: CPET

Interventions

MSOT - Multispectral optoacustic tomography DIAGNOSTIC_TEST

MSOT is an advanced imaging technology that combines laser-induced ultrasound and light absorption to visualize biological tissues. By detecting ultrasound waves generated from tissue absorption of multispectral light, MSOT provides high-resolution, real-time images with functional and molecular information. One of its use is in biomedical research and clinical applications to study blood oxygenation and tissue composition, making it valuable for areas such as vascular research. In this study, we aim to utilize MSOT to differentiate between venous, arteriovenous and lymphatic malformations.

PAD - peripheral artery disease; Strength athletes; Triathletes; older, unathletic group; training PAD Patients; young, unathletic group

CPET DIAGNOSTIC_TEST

Spiroergometry (also called cardiopulmonary exercise testing, CPET) is a diagnostic test that measures how the heart, lungs, and muscles work together during physical activity. While a person performs exercise treadmill the test records breathing gases (oxygen uptake and carbon dioxide output), ventilation, heart rate, and workload. It provides valuable information about aerobic capacity, endurance, and limitations caused by cardiovascular, pulmonary, or metabolic conditions, making it useful in sports medicine, rehabilitation, and clinical diagnostics.

PAD - peripheral artery disease; Strength athletes; Triathletes; older, unathletic group; training PAD Patients; young, unathletic group

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study will include adult participants aged 18 to 75 years, representing different levels of physical activity and vascular health status. A total of approximately 60 participants will be recruited, divided into six cohorts of about ten individuals each. Cohort Description: * Young endurance athletes (≥ 3 times per week, ≥ 60 minutes per session) Examples: running, cycling, swimming * Young strength athletes (≥ 3 times per week, ≥ 60 minutes) No additional endurance training * Young healthy controls Less than 2 times per week and \< 30 minutes of physical activity No known vascular or muscular diseases * Patients with peripheral arterial disease (PAD) Diagnosed with PAD, Fontaine stage I, IIa or IIb * Older inactive controls Age above 55 years, no regular physical activity, no pAVK * Patients with PAD (Fontaine stage I, IIa or IIb, who participate in structured walking training

You may qualify if:

• Age ≥ 18 years (adults capable of giving consent)
• Capacity to consent. The subjects are able to understand the information provided and give their written consent.
• Belonging to one of the following cohorts:
• Endurance athletes: at least 3× per week ≥ 60 minutes of intensive endurance training (e.g., running, cycling, swimming)
• Strength athletes: at least 3× per week ≥ 60 minutes of intensive strength training without additional endurance training
• Healthy control subjects: less than 2× per week \< 30 minutes of physical activity, no known vascular diseases
• PAD patients: diagnosed peripheral arterial occlusive disease in Fontaine stage I or IIa Women of childbearing age with or without contraception may participate, as there are no risks of harm to the fetus.
• Consent to pseudonymized data collection and storage in accordance with the GDPR.

You may not qualify if:

• Age over 75 years
• Minors (Age \< 18)
• safety concerns on the part of the study physician, e.g., in the case of of: physical, mental or psychiatric illnesses, acute or chronic conditions that could jeopardise safety or data quality
• Taking medications that could affect physical performance or physiological measurements (e.g., heart rate, oxygen uptake).
• Pregnancy with known risks or complications (participation is possible in principle, but subject to individual medical review).
• Refusal to participate or lack of informed consent.

Sponsors & Collaborators

• University Hospital Erlangen: lead
• PD Dr. med. Ferdinand Knieling, Department of pediatrics, University of Erlangen-Nürnberg: collaborator

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Consultant, Department of Vascular Surgery, University Hospital Erlangen

Study Record Dates

• First Submitted: December 11, 2025
• First Posted: January 16, 2026
• Study Start: January 1, 2026
• Primary Completion: March 1, 2026
• Study Completion (Estimated): August 1, 2026
• Last Updated: January 16, 2026

Record last verified: 2026-01