Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621001061820
Ethics application status
Approved
Date submitted
28/06/2021
Date registered
12/08/2021
Date last updated
12/08/2021
Date data sharing statement initially provided
12/08/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Measurement of breath-by-breath respiration from pacemaker lead impedance data
Scientific title
Measurement of breath-by-breath respiration from pacemaker lead impedance data in adults with Boston Scientific pacemakers.
Secondary ID [1] 304626 0
Nil Known
Universal Trial Number (UTN)
U1111-1266-8177
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Heart failure requiring pacemaker insertion. 322553 0
Cardiac conduction disorders requiring pacemaker insertion. 322554 0
Condition category
Condition code
Cardiovascular 320178 320178 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This trial does not fit neatly into either of the observational or interventional categories. The purpose of this trial is to see whether or not Boston Scientific pacemakers with the ability to measure minute ventilation have accurate enough detection of ventilation to discern each inhalation from each exhalation. To do this, we will apply a respiratory band across each patient's chest. This will serve as the gold standard measurement of inhalation and exhalation, against which the data from the Boston Scientific pacemakers will be compared.

To discern whether or not the pacemakers can accurately detect each breath cycle through a range of respiratory rates, we will ask each patient to breathe normally, hold their breath, breathe slowly and breathe rapidly. Will also ask them to swallow water and to laugh to see if these manoeuvres affect the accuracy of inhalation/exhalation detection. We will then ask each patient to walk on a treadmill for 6 minutes to see if motion affects the accuracy of the measurement.

We will be observing the signals from the patients' pacemakers but will also be intervening in that we will ask them to perform the aforementioned tasks. There are no intervention/control groups.

First, the normal breathing pattern of the patient will be observed for 30 seconds. We will then ask the patient to breathe in sync with the signals coming from an audiovisual metronome. First, the metronome will be set at 20 breaths per minute for 30 seconds. We will then allow the patient a period of rest to recover from the rapid breathing. After that, we will again ask them to synch their breath to the audiovisual metronome signal that is set to 8 breaths per minute for 32 seconds. After another period of recovery, we will ask the patient to hold their breath for 15 seconds. After a period of recovery, we will ask them to drink a cup of water. After that, we will ask them to simulate laughter and/or tell them a joke. Finally, we will ask them to walk at a speed of 5 km/h for 6 minutes.

The minute ventilation data from the Boston Scientific pacemaker will undoubtedly include environmental noise that will be interfering with the respiration signal. We will use the pacemaker lead electrogram signal to filter out the noise caused by the pacemaker pacing signal. We will use an electrocardiogram to filter out the noise caused by the electrical activity and contraction of the heart. We will work with bioengineers from the Auckland Bioengineering Institute of Auckland University to develop mathematical methods to filter out the noise from other sources. This will hopefully leave us with filtered data that represents the patient's breathing.

Patient's with Boston Scientific pacemakers who are attending pacemaker clinic at Waikato Hospital will be recruited. Measurements for the purpose of this research will be taken after the routine pacemaker check is complete and only when the pacemaker check is considered to be "normal". Experienced clinical cardiac physiology staff who run Waikato Hospital's pacemaker clinics will be present at all times during the data collection sessions to ensure patient safety and to help with the data collection.

Each patient who consents will have their measurements recorded once. We estimate that the entire protocol will take 15-20 minutes to complete.
Intervention code [1] 320980 0
Treatment: Devices
Comparator / control treatment
Each patient will serve as their own control as the respiratory band applied across their chest will serve as the gold standard measurement of their respiration against which the pacemaker measurements will be compared.
Control group
Active

Outcomes
Primary outcome [1] 328077 0
The primary outcome will be the level of agreement with regards to the detected respiratory cycle phase between the respiratory band and the pacemaker impedance data.

This will be measured through mathematical analysis of the sinusoidal waves representing the respiratory band data and the pacemaker impedance data.
Timepoint [1] 328077 0
During the patients' pacemaker clinic appointment.
Secondary outcome [1] 397513 0
Whether or not there is a delay between the pacemaker detection of each inspiration/expiration and the respiratory band detection of each inhalation/exhalation. If so, how large is this delay? This is a composite secondary outcome.

This will be measured by comparing the nadir and zenith timing of the sinusoidal waves representing the respiratory band data and the pacemaker impedance data.
Timepoint [1] 397513 0
During the patients' pacemaker clinic appointment.

Eligibility
Key inclusion criteria
1) Be at least 18 years old.
2) Have a Boston Scientific pacemaker/implantable cardioverter defibrillator capable of measuring minute ventilation.
2) Can comply with the breathing exercises.
3) Are likely able to walk on a treadmill for 6 minutes without discomfort.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1) People who have any medical conditions that stop them from being able to hold their breath for a short period of time.
2) Find it difficult or painful to walk.
3) Those who do not consent to their information being collected and used for the purposes of this research.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised 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
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
In order to develop the exact statistical methods for this study, we first need to recruit patients and acquire their pacemaker minute ventilation data. This data will include environmental noise and the statistical methods needed to filter out that noise are dependent on the data itself/the types of noise present. We need the pacemaker data to figure out the optimal techniques to filter the noise out.

This research aims to ascertain whether or not current Boston Scientific pacemakers enable accurate enough respiration measurements to discern inspiration from expiration during any given breath. The data from a respiration band around the patient's chest will be used as our gold standard, against which the data from the pacemaker will be evaluated.

We will obtain data from patients using:
1) The minute ventilation data from their pacemakers
2) Pacemaker electrogram
3) Respiration band around the patient's chest
4) Electrocardiogram
5) Height and weight measurements

The minute ventilation data from the patient's pacemaker will certainly include interfering and useless signals which we will have to filter out.

We will use the data obtained from the pacemaker electrogram and the electrocardiogram to filter out the noise from predictable sources such as the pacing signal from the pacemaker itself and the contraction of the myocardium. Once the noise from predictable sources has been filtered out, we will work with Bioengineers from the Auckland University Bioengineering Institute to develop methods to filter out the unpredictable noise. We cannot comment on the exact techniques that will be used to do this at this time, as the techniques will vary depending on the type of noise present. We will first need to obtain the data from patients to develop these methods.

Once all of the noise from the pacemaker data has been filtered out, we will analyse the filtered pacemaker data by comparing its frequency and time domain characteristics to the respiratory band data's frequency and time domain characteristics. This will allow us to ascertain the exact relationship between the pacemaker respiration data and the respiration band data, i.e. can the pacemaker reliably detect both inspiration and expiration in the first place? Can the pacemaker do this through a range of breathing frequencies and while the body is in motion? If so, does the pacemaker data need a correction factor to represent a true inhalation/exhalation more accurately?

To help us better understand the signals from the pacemaker, we will also stratify patients based on their age, gender, ethnicity and BMI. These subgroup analyses will enable us to determine whether or not and to what extent these characteristics affect the pacemaker data.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
26/08/2021
Actual
Date of last participant enrolment
Anticipated
29/10/2021
Actual
Date of last data collection
Anticipated
29/10/2021
Actual
Sample size
Target
50
Accrual to date
Final
Recruitment outside Australia
Country [1] 23926 0
New Zealand
State/province [1] 23926 0
Waikato

Funding & Sponsors
Funding source category [1] 308986 0
Hospital
Name [1] 308986 0
Waikato Hospital
Country [1] 308986 0
New Zealand
Primary sponsor type
Individual
Name
Khashayar Ghafouri
Address
Waikato Clinic Campus, Waikato Hospital, Pembroke Street, 183 Pembroke Street, Hamilton 3204
Country
New Zealand
Secondary sponsor category [1] 309941 0
None
Name [1] 309941 0
NA
Address [1] 309941 0
NA
Country [1] 309941 0
Other collaborator category [1] 281891 0
Individual
Name [1] 281891 0
A/Prof. Martin K Stiles.
Address [1] 281891 0
Waikato Hospital, 183 Pembroke Street, Hamilton 3204
Country [1] 281891 0
New Zealand
Other collaborator category [2] 281892 0
Individual
Name [2] 281892 0
Prof. Julian F. R. Paton
Address [2] 281892 0
The University of Auckland Grafton Campus, 85 Park Road, Grafton.
Country [2] 281892 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 308877 0
Southern Health and Disability Ethics Committee
Ethics committee address [1] 308877 0
Ministry of Health, 133 Molesworth Street, Wellington, 6011 PO Box 5013.
Ethics committee country [1] 308877 0
New Zealand
Date submitted for ethics approval [1] 308877 0
23/04/2021
Approval date [1] 308877 0
25/05/2021
Ethics approval number [1] 308877 0
21/STH/101

Summary
Brief summary
In this trial, we aim to determine whether or not your pacemaker can provide accurate data on your breathing. In a healthy heart, the rhythm of the heartbeat is in sync with the breath. This synchronicity is reduced with age and lost in heart disease. Recent research has shown that restoring the link between the heart rate and the breath can significantly improve a failing heart's performance in animals. If your current pacemaker proves to be accurate in its measurements of your breathing, we could use this technology to allow future pacemakers to mimic the natural breathing rhythm of the heart. By doing this, we hope that future pacemakers will give patients a better quality of life and reduce the symptoms they experience daily.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 112194 0
A/Prof Martin K. Stiles
Address 112194 0
Waikato Clinical Campus, Waikato Hospital, 183 Pembroke Street, Hamilton, New Zealand, 3204.
Country 112194 0
New Zealand
Phone 112194 0
+64 7 8398899
Fax 112194 0
Email 112194 0
[email protected]
Contact person for public queries
Name 112195 0
Mr Khashayar Ghafouri
Address 112195 0
Waikato Clinical Campus, Waikato Hospital, 183 Pembroke Street, Hamilton, New Zealand, 3204.
Country 112195 0
New Zealand
Phone 112195 0
+64 7 8398899
Fax 112195 0
Email 112195 0
[email protected]
Contact person for scientific queries
Name 112196 0
A/Prof Martin K. Stiles
Address 112196 0
Waikato Clinical Campus, Waikato Hospital, 183 Pembroke Street, Hamilton, New Zealand, 3204.
Country 112196 0
New Zealand
Phone 112196 0
+64 7 8398899
Fax 112196 0
Email 112196 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
We do not have the ethics committee clearance to share patient data.


What supporting documents are/will be available?

No Supporting Document Provided



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.