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Trial registered on ANZCTR


Registration number
ACTRN12623000460606
Ethics application status
Approved
Date submitted
13/04/2023
Date registered
4/05/2023
Date last updated
4/05/2023
Date data sharing statement initially provided
4/05/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
Hot Legs in Heart Failure: Examining Changes in Core Temperature and Lower Limb Blood Flow in lower limb immersion therapy
Scientific title
Hot Legs in Heart Failure: Examining Changes in Core Temperature and Lower Limb Blood Flow
Secondary ID [1] 309433 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Heart failure with Reduced Ejection Fraction 329688 0
Condition category
Condition code
Cardiovascular 326584 326584 0 0
Coronary heart disease

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study intervention will involve 45 minutes of lower limb immersion in either thermoneutral (30°C) or hot water (40°C) bath.
We will be using a water tank (container) that will connected with ICool System that will maintain the set temperature throughout 45 mins of immersion. Participants will immerse their both legs in water tank which will be filled up to either knee or ankle height (randomly assigned).

During the intervention participants will be seated on the chair with their both legs immersed in the water. We have set up the lab with a wall mounted TV screen (at eye level) that participants can watch during 45 minutes of water immersion.

Our research team comprises researchers with experience in undertaking hot water immersion interventions, additionally all the interventions will be supervised by a physiotherapist.

The water temperature will set to desired level prior to the immersion. We will be using an ICool system that circulates the water between the system and the container to maintain the desired temperature throughout the set period. Water temperature will be monitored throughout the experiment through the digital monitor on the ICool System.

As detailed previously, we have undertaken a similar pilot study in establishing this protocol and our team includes physiotherapist, exercise physiologist and clinical physiologists will expertise in undertaking similar interventions in individuals cardiorespiratory conditions.

The study will involve 5 experimental visits - a familiarisation visit and 4 experimental visits with a week interval between the visits to allow washout.
Visit 1 (familiarisation visit): This visit will involve obtaining the informed written consent and familiarising the participants to the research protocol. Participants will be detailed about all the intervention involved before getting the consent signed. After obtaining the informed written consent, we will obtain the anthropometric measurements and set the height of the table ensuring the comfortable posture while legs are immersed in the water tank. We will also measure the baseline Vascular function and skeletal muscle tissue oxygenation.

Visits 2 to 5: during these 4 weekly sessions participants will undertake four 45 mins hot water interventions in random order. The interventions are: (1) Angle height thermoneutral (30 degree C), (2) Ankle height hot (40 degree C), (3) Knee height thermoneutral (30 degree C) and (4) Knee height hot (40 degree C).

Each intervention will take 45 mins. Thermal response will be monitored during the intervention and on the completion of each intervention vascular function and skeletal muscle tissue oxygenation will be measured.
Intervention code [1] 325863 0
Rehabilitation
Comparator / control treatment
Self Controlled study, the comparison will be made between Thermoneutral (reference comparator) and hot water immersion groups.
Control group
Placebo

Outcomes
Primary outcome [1] 334442 0
Thermal Responses:
Core temperature will be monitored using a telemetric temperature sensor capsule (BodyCap®, Caen, France) ingested 2-3 hours prior to the study.
Timepoint [1] 334442 0
Thermal responses will be monitored during visits 2-5

Thermal response will be monitored continuously though a telemetric temperature sensor capsule. Temperature will be monitored from 30 min prior to water immersion and measurement will be stopped after the completion of immersion intervention once the temperature returns to the baseline.
Primary outcome [2] 334600 0
Skin Temperature (visits 2-5):
Skin temperature will be measured using thermistors placed on the arm and leg (MLT422/A; ADInstruments, Bella Vista, NSW, Australia) and skin blood flow measured using laser-Doppler flowmetry with the probe placed on the forearm.
Timepoint [2] 334600 0
Skin Temperature (visits 2-5):
Skin temperature will monitored every 5min during the water immersion and will continue till the skin temperature return back to baseline on the completion of immersion protocol.
Secondary outcome [1] 420637 0
Vascular Function. Blood flow and flow-mediated dilation of the popliteal, superficial femoral, and brachial arteries will be assessed using a Vivid E9 ultrasound system (GE Healthcare) equipped with a 15 MHz linear-array transducer.


Blood flow and flow-mediated dilation are composite secondary outcome.
Timepoint [1] 420637 0
During visits 2-5 after the immersion protocol

Vascular function (ultrasound) will be undertaken following the completion of immersion protocol during each visit.
Secondary outcome [2] 420638 0
Skeletal muscle tissue oxygenation: Near-infrared spectroscopy (NIRS): (tissue oxygen saturation and muscle deoxygenation kinetics of the gastrocnemius and vastus lateralis muscles) will be assessed at rest (Portamon, Artinis Medical Systems).
Timepoint [2] 420638 0
During visits 2-5
The Near Infrared Spectroscopy (NIRS) measurement for tissue oxygenation will undertake following the completion of immersion protocol on each visit.

Eligibility
Key inclusion criteria
• A referral to HF rehabilitation
• NYHA class I-III, heart failure with reduced ejection fraction HFrEF)
• Aged greater than 18 years
• No exacerbations of HF-related symptoms or changes in medications within the past 3 months
• Free from unstable angina, recent myocardial infarction or severe valvular disease
• No skin conditions that would prevent limb immersion in water bath.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• Participants with exacerbation of HF symptoms or changes in medications within the past 3 months
• HF participants with unstable angina, recent myocardial infarction or severe valvular disease
• HF participants with skin conditions that would prevent limb immersion in water bath
• Unable to use the ingestible telemetry pill for measuring core temperature (ie individuals: with surgically implanted electro-medical devices: body mass less than 40kg, with gastrointestinal surgery or disorders (e.g., Chron's, diverticula, motility issues), have expected/scheduled MRI scanning in within 72h of ingestion, are pregnant

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
central randomisation
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Descriptive data will be expressed as mean±SD (normally distributed) or median and interquartile range (non-normal distribution). To evaluate the impact of the lower limb heating and water height on primary and secondary outcome measures, a paired t-test will be performed (normally distributed data) or a Wilcoxon (non-parametric equivalent). The probability of a type I error will be set at 5% (a=0.05).

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment postcode(s) [1] 40086 0
4215 - Southport
Recruitment postcode(s) [2] 40087 0
4217 - Gold Coast

Funding & Sponsors
Funding source category [1] 313627 0
University
Name [1] 313627 0
Griffith University
Country [1] 313627 0
Australia
Primary sponsor type
University
Name
Griffith University, Menzies Health Institute Queensland
Address
Griffith Univeristy
Parklands Drive, QLD 4215
Country
Australia
Secondary sponsor category [1] 315421 0
None
Name [1] 315421 0
NONE
Address [1] 315421 0
NONE
Country [1] 315421 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 312799 0
Griffith University Human Research Ethics Committee (GUHREC
Ethics committee address [1] 312799 0
Research Ethics and Integrity Office for Research Griffith University
Nathan campus, Griffith University
170 Kessels Road QLD 4111, Australia
Ethics committee country [1] 312799 0
Australia
Date submitted for ethics approval [1] 312799 0
08/12/2022
Approval date [1] 312799 0
08/03/2023
Ethics approval number [1] 312799 0
GU Ref No: 2022/910

Summary
Brief summary
The proposed study will evaluate whether 45 minutes of lower limb heating at 40°C upregulates the thermal response (i.e., core temperature, skin temperature, skin blood flow), vascular function (lower an upper limb) and skeletal muscle tissue oxygenation in HF patients with reduced ejection fraction. A secondary aim is to compare the effect of water height (ankle vs knee) on thermal and vascular function and skeletal muscle of oxygenation.

The study will 5 separate visits to Griffith University (approximately 5 hours in total). These will entail an initial baseline assessment (approximately 30 mins), followed by another 4 visits (approximately 60 mins) of lower limb immersion with measurements of core temperature and blood flow. For research visits 2-5, The lower limb immersion will be undertaken at thermoneutral (water temperature 30°C) or hot (water temperature 40°C) lower limb immersion with water up to ankle or knee height.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 125966 0
Prof Norman R Morris
Address 125966 0
School of Health Sciences and Social Work
The Menzies Health Institute
Griffith University
1 Parklands Dr, Southport QLD 4215


Country 125966 0
Australia
Phone 125966 0
+61 756780162
Fax 125966 0
Email 125966 0
n.morris@griffith.edu.au
Contact person for public queries
Name 125967 0
Prof Norman R Morris
Address 125967 0
School of Health Sciences and Social Work
The Menzies Health Institute
Griffith University
1 Parklands Dr, Southport QLD 4215
Country 125967 0
Australia
Phone 125967 0
+61 756780162
Fax 125967 0
Email 125967 0
n.morris@griffith.edu.au
Contact person for scientific queries
Name 125968 0
Prof Norman R Morris
Address 125968 0
School of Health Sciences and Social Work
The Menzies Health Institute
Griffith University
1 Parklands Dr, Southport QLD 4215
Country 125968 0
Australia
Phone 125968 0
+61 756780162
Fax 125968 0
Email 125968 0
n.morris@griffith.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
De identified participant data collected during the study.
When will data be available (start and end dates)?
Immediately following the publication, no end date.
Available to whom?
Researchers who provide a methodologically sound proposal, on a case-by-case basis at the discretion of Primary Sponsor.
Available for what types of analyses?
Any purpose, only for the achievement of the aims in the approved proposal
How or where can data be obtained?
Access subject to approval of the Principal Investigator.
Prof Norman Morris
School of Health Sciences and Social Work
The Menzies Health Institute
Griffith University
n.morris@griffith.edu.au


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
18836Study protocol    385727-(Uploaded-11-04-2023-18-17-19)-Study-related document.docx
18838Informed consent form    385727-(Uploaded-19-04-2023-16-36-50)-Study-related document.docx



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.