Impedance Plethysmography Based Deep Vein Thrombosis Monitoring During Catheter-directed Thrombolysis

NCT07665320 | Recruiting

• 1 other identifier: ThrombUS+B4
• Study Type: observational
• Target: 40
• Locations: 1 country
• Sites: 2

Brief Summary

The purpose of this study is to collect data on blood circulation using a multi-frequency impedance plethysmography device developed in the ThrombUS+ project. Impedance plethysmography (IPG) is a non-invasive method that measures changes in blood volume using electrodes placed on the skin. The collected data will be used for device development, the improvement of diagnostic data analysis methods, and AI training. A total of 40 participants will be recruited for this study, with 20 healthy volunteers in Tampere University and 20 patients undergoing thrombolytic therapy for DVT at Tampere University Hospital.

Conditions

Deep Vein Thrombosis (DVT)

Keywords

deep vein thrombosis; DVT

Outcome Measures

Primary Outcomes (2)

• Impedance plethysmography (IPG) data during CDT treatment

  From enrollment to the end of the CDT treatment (up to 2 days)

• Impedance plethysmography (IPG) data from healthy volunteers

  From enrollment to the end of measurements (up to 2 hours)

Study Arms (2)

Patients

DVT detected on other lower limb, undergoing catheter-directed thrombolysis

Device: Impedance plethysmography IPG; Device: Venous Occlusion Plethysmography VOP; Other: Breathing and leg movement exercise

Healthy volunteers

Healthy volunteers

Device: Impedance plethysmography IPG; Device: Venous Occlusion Plethysmography VOP; Other: Breathing and leg movement exercise

Interventions

Breathing and leg movement exercise OTHER

The first exercise is the Valsalva maneuver, where the subject first inhales and then pushes out the breath while the larynx is closed. In the second exercise, the subject inhales for approximately 10 seconds, holds the breath for approximately 5 seconds, and then breathes out. Finally, the subject moves the ankles to contract calf muscles, and further to cause changes in venous blood volume. The IPG signal is measured on both calves by ThrombUS+ prototype device during these exercises.

Also known as: Valsalva

Healthy volunteers; Patients

Impedance plethysmography IPG DEVICE

IPG signal is measured with ThrombUS+ prototype device

Also known as: IPG

Healthy volunteers; Patients

Venous Occlusion Plethysmography VOP DEVICE

In VOP measurement, a temporal blood restriction is caused by an occlusive cuff blocking venous outflow but allowing arterial inflow. The cuff intervention causes a change in venous blood volume, and it can be measured by electrical impedance plethysmography (IPG).

Also known as: VOP

Healthy volunteers; Patients

Eligibility Criteria

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

Study Population

Tampere

You may qualify if:

• Age: 18 or older;
• DVT detected on other lower limb;
• Suitable for CDT treatment;
• Ability to give informed consent;
• Volunteering for the study.

You may not qualify if:

• Age under 18 years;
• Inability to give informed consent;
• Denial;
• Too injured skin in the measurement area
• Age: 18 or older;
• Ability to give informed consent;
• Volunteering for the study
• Diagnosed DVT in lower limbs;
• Age under 18 years;
• Inability to give informed consent;
• Denial;
• Too injured skin in the measurement area.

Sponsors & Collaborators

• Tampere University: lead
• Tampere University Hospital: collaborator

Study Sites (2)

Tampere University Hospital

Tampere, Finland

RECRUITING

Tampere University

Tampere, Finland

COMPLETED

MeSH Terms

Conditions

Venous Thrombosis

Interventions

Plethysmography, Impedance; Respiration; Valsalva Maneuver

Condition Hierarchy (Ancestors)

Thrombosis; Embolism and Thrombosis; Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Plethysmography; Diagnostic Techniques, Cardiovascular; Diagnostic Techniques and Procedures; Diagnosis; Electrodiagnosis; Respiratory Physiological Phenomena; Circulatory and Respiratory Physiological Phenomena; Heart Function Tests; Respiratory Function Tests; Diagnostic Techniques, Respiratory System; Hemodynamics; Cardiovascular Physiological Phenomena

Central Study Contacts

Vehkaoja

CONTACT

+358407393181; antti.vehkaoja@tuni.fi

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: May 15, 2026
• First Posted: June 24, 2026
• Study Start: July 17, 2025
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027
• Last Updated: June 29, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

FI (2)