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Trial registered on ANZCTR


Registration number
ACTRN12613000361707
Ethics application status
Approved
Date submitted
18/12/2012
Date registered
5/04/2013
Date last updated
3/08/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
The impact of whole body heating on blood flow distribution and temperature regulation in chronic heart failure patients
Scientific title
The effect of repeated whole body heating on blood flow distribution to skin, muscle and cerebral vessel beds and thermoregulatory responses in chronic heart failure patients.
Secondary ID [1] 281165 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
New York Heart Association Class I-III chronic heart failure (aetiology either ischaemic or idiopathic dilated cardiomyopathy) 287331 0
Condition category
Condition code
Cardiovascular 287667 287667 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Responses to warm water immersion (maintained at a constant temperature of approximately 36 degrees celcius), to the waist level for a period of 30 minutes. During this period, skeletal muscle, cerebral and skin blood flows will be measured as well as sweat rate production and core temperature changes.

Subsequently, the warm water heating protocol will be repeated 3 times per week for a period of 10 weeks. CHF subjects will be randomised to either the warm water heating in a bath for 30 minutes 3 times a week or to a euthermic bath control group.

Warm water immersion will be conducted in custom-made water bath, whereby participants will sit immersed in water to the waist level. This method of heating the body has been chosen because it allows the study to be performed in a supervised environment. It also allows us to measure the effect of heating on the whole body, including body parts not immersed in the heating stimulus (i.e. the arms, which will be kept out of the water). The bath temperature will be similar to that which would be experienced in a warm bath or spa at home (ie 32-38 degrees C). The water temperature is thermostatically controlled using specialised equipment (iCool, Queensland). Blood pressure and heart rate will be continuously monitored during these sessions to provide information regarding each subject's tolerance of the warm bath. If this becomes uncomfortable at any stage, the water temperature will be cooled or the participant will be allowed to leave the bath.

The group allocated to the euthermic water exposure will be positioned in an identical custom-made bath for 30 minutes and will be monitored in an identical fashion to those allocated to warm water immersion, however, the temperature of the water in the euthermic group will be thermostatically controlled to room temperature using specialised equipment (iCool, Queensland).

Intervention code [1] 285612 0
Treatment: Other
Intervention code [2] 285613 0
Rehabilitation
Comparator / control treatment
In the observational element of the study (a preliminary assessment which will take place prior to the start of the 10-week intervention) haemodynamic and thermoregulator responses to 30 minutes of acute heat (warm water; approximately 36 degrees Celsius) exposure will be assessed in CHF and matched healthy control subjects to provide a basis for determination of differences in blood perfusion and thermoregulation due to CHF.

In the interventional element of the study, CHF subjects will be randomised to either the warm water heating (approximately 36 degrees Celsius) in a bath for 30 minutes 3 times a week or to a euthermic bath control group (approximately 28 degrees Celsius). The control group will be exposed to euthermic water immersion for 30 minutes 3 times a week to allow us to investigate the impact of water immersion per se.
Control group
Active

Outcomes
Primary outcome [1] 288479 0
Brachial, carotid and cerebral artery blood flow asssesed by high resolution ultrasonography
Timepoint [1] 288479 0
At baseline prior to randomisation and following the 10 week intervention. Additionally measurements will be taken at fortnightly intervals during the intervention.
Primary outcome [2] 288488 0
Skin blood flow assessed by microdialysis infusion of locally acting blocking agents and laser Doppler flowmetry.
Timepoint [2] 288488 0
At baseline prior to randomisation and following the 10 week intervention. Additionally measurements will be taken at fortnightly intervals during the intervention.
Primary outcome [3] 288489 0
Sweat rate production assessed by a water vapour vapour pressure sensitive capacitor.
Timepoint [3] 288489 0
At baseline prior to randomisation and following the 10 week intervention. Additionally measurements will be taken at fortnightly intervals during the intervention.
Secondary outcome [1] 300271 0
Skin and core body temperature assessed using external (skin) and internal (rectal) thermistors.
Timepoint [1] 300271 0
At baseline prior to randomisation and following the 10 week intervention. Additionally measurements will be taken at fortnightly intervals during the intervention.

Eligibility
Key inclusion criteria
Patients with New York Heart Association Class I-III CHF (aetiology either ischaemic or idiopathic dilated cardiomyopathy)


A group of subjects who do not have CHF will be recruited as controls. These control subjects will be matched for age, sex and body composition.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria

Recent history of syncope (past 6 months)
Systolic blood pressure < 90mmHg
New York Heart Association Class IV
Recent exacerbation of heart failure resulting in hospitalisation (< 2months)

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)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint(s)
Statistical methods / analysis

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)
WA

Funding & Sponsors
Funding source category [1] 286450 0
Charities/Societies/Foundations
Name [1] 286450 0
National Heart Foundation
Address [1] 286450 0
National Heart Foundation
334 Rokeby Road
Subiaco
Perth
Western Australia
6008
Country [1] 286450 0
Australia
Primary sponsor type
Hospital
Name
Royal Perth Hospital
Address
Royal Perth Hospital
197 Wellington Street
Perth
Western Australia
6000
Country
Australia
Secondary sponsor category [1] 285238 0
University
Name [1] 285238 0
University of Western Australia
Address [1] 285238 0
University of Western Australia
35 Stirling Highway
Crawley
Perth
Western Australia
6009
Country [1] 285238 0
Australia

Ethics approval
Ethics application status
Approved

Summary
Brief summary
Patients with chronic heart failure (CHF) have an impaired capacity to regulate body temperature. This study will investigate the acute effects of body heating in patients with CHF and also the effects of repetitive exposure to whole body heating. Participants will be recruited from general Cardiology at RPH, from private Cardiology clinics and from the Cardiac Transplant Unit and Advanced Heart Failure Service at RPH.

Study hypotheses:
1. Patients with CHF will exhibit impaired cardiovascular responses to an acute bout of body heating, compared to age, gender and BMI matched controls.

2. Repeated whole body heating will improve abnormal cardiovascular function evident in response to body heating in patients with CHF.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 34664 0
Dr Andrew Maiorana
Address 34664 0
Cardiac Transplant Unit
Royal Perth Hospital
197 Wellington Street
Perth
Western Australia
6000

Country 34664 0
Australia
Phone 34664 0
+61 0433567369
Fax 34664 0
Email 34664 0
Andrew.Maiorana@health.wa.gov.au
Contact person for public queries
Name 17911 0
Dr Andrew Maiorana
Address 17911 0
Royal Perth Hospital
197 Wellington Street
Perth
Western Australia
6000
Country 17911 0
Australia
Phone 17911 0
+61 0433567369
Fax 17911 0
Email 17911 0
Andrew.Maiorana@health.wa.gov.au
Contact person for scientific queries
Name 8839 0
Dr Andrew Maiorana
Address 8839 0
Royal Perth Hospital
197 Wellington Street
Perth
Western Australia
6000
Country 8839 0
Australia
Phone 8839 0
+61 0433567369
Fax 8839 0
Email 8839 0
Andrew.Maiorana@health.wa.gov.au

No information has been provided regarding IPD availability
Summary results
No Results