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Recruiting NCT07665320

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

— Observational Deep Vein Thrombosis (DVT)

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Impedance plethysmography IPG, Venous Occlusion Plethysmography VOP, Breathing and leg movement exercise.
Who it may be relevant to
Registry conditions: Deep Vein Thrombosis (DVT). Basic parameters: from 18 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Finland
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Unsure about the terms? Read our patient guide →

Overview

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.

Detailed description

This study aims to collect IPG data set from healthy volunteers and DVT patients using ThrombUS+ prototype device developed during the project and commercial IPG device as a reference. The data will be used to develop ThrombUS+ IPG device, its signal processing and analysis algorithms and to train ML models.

Objectives of the study are to

1. Collect IPG data for developing signal processing, data analysis and ML algorithms for DVT detection and assessment. 2. Evaluate the performance of the developed methods to gold standard references including angiography, ultrasound imaging and venous occlusion plethysmography. 3. Investigate whether multi-frequency IPG measurement improves the performance of DVT detection compared to single frequency measurement and determine the optimal measurement frequency. 4. Investigate and compare different interventions to cause changes in venous blood volume for DVT detection, such as venous occlusion by thigh cuff, active respiration and muscle activation.

Secondary objectives are

1\) To investigate methods for simulating DVT and to compare the performance of these methods for DVT simulation.

Interventions

  • Device Impedance plethysmography IPG
    IPG signal is measured with ThrombUS+ prototype device
  • Device Venous Occlusion Plethysmography VOP
    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).
  • Other Breathing and leg movement exercise
    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.

Primary outcome measures

  • Impedance plethysmography (IPG) data during CDT treatment [Time frame: From enrollment to the end of the CDT treatment (up to 2 days)]
  • Impedance plethysmography (IPG) data from healthy volunteers [Time frame: From enrollment to the end of measurements (up to 2 hours)]

Eligibility criteria

Inclusion Criteria for Patients group:

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

Exclusion Criteria for Patients group:

  • Age under 18 years;
  • Inability to give informed consent;
  • Denial;
  • Too injured skin in the measurement area

Inclusion Criteria for Healthy volunteers group:

  • Age: 18 or older;
  • Ability to give informed consent;
  • Volunteering for the study

Exclusion Criteria for Healthy volunteers group:

  • Diagnosed DVT in lower limbs;
  • Age under 18 years;
  • Inability to give informed consent;
  • Denial;
  • Too injured skin in the measurement area.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model
Cohort

Study locations

Finland · 2 centers
  • Tampere University Hospital — Tampere
  • Tampere University — Tampere

Identifiers

NCT: NCT07665320 · ThrombUS+B4

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗