ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12626001335381

Ethics application status

Approved

Date submitted

13/10/2026

Date registered

5/11/2026

Date last updated

5/11/2026

Date data sharing statement initially provided

5/11/2026

Type of registration

Prospectively registered

Titles & IDs

Public title

Advanced imaging of the sympathetic nervous system in people with hypertension

Scientific title

Advanced imaging of the sympathetic nervous system in people with hypertension

Additional trial identifiers [1]

Nil

Universal Trial Number (UTN)

Trial acronym

Related trial records

Health condition

Health condition(s) studied:

Hypertension

Cardiovascular disease

Condition category

Condition code

Cardiovascular

Hypertension

Cardiovascular

Other cardiovascular diseases

Intervention/exposure

Study type

Interventional

Description of the intervention or exposure

Visit 1 will include a baseline assessment and MSNA (see comparator description). Visit 2 will include a 24-hour blood pressure monitor. Visit 3 will involve a Magnetic resonance imaging (MRI) scan and Ga68 Prostate Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET) scan.

Magnetic resonance imaging (MRI) scan. This involves lying flat in an MRI scanner for approximately 15 minutes. No contrast is used. Ga68 Prostate Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET) scan. This will involve injection of Ga68 PSMA intravenously, resting for one hour, and then laying still under a PET camera for up to 1 hour. Both scans are performed at the same visit, and once only. Scans are performed at a research imaging facility with expertise and experience in performing scans. Scans will be performed within 4 weeks of baseline visit.

24-hour blood pressure monitors will be performed once only within 4 weeks of baseline visit. Participants will be instructed how to use this by study staff.

Intervention code [1]

Diagnosis / Prognosis

Intervention code [2]

Early detection / Screening

Description of the comparator or control

Muscle Sympathetic Nerve Activity (MSNA) testing - a microelectrode is inserted into the peripheral nerve to allow measurement of electrical nerve impulses from the sympathetic nervous system. The procedure may take up to 2 hours. This procedure will happen once, at baseline, and be performed by a trained member of the study staff.

Age and gender matched healthy control cohort will undergo the same interventions.

Control group

Active

Outcomes

Primary outcome [1]

Coeliac ganglia volume

Timepoint [1]

Within 4 weeks of baseline at the time of MRI imaging - Visit 3

Primary outcome [2]

Coeliac ganglia fat fraction

Timepoint [2]

Within 4 weeks of baseline at the time of MRI imaging - Visit 3

Primary outcome [3]

Coeliac ganglia radiotracer activity

Timepoint [3]

Within 4 weeks of baseline at the time of Ga68 PSMA PET imaging - Visit 3

Secondary outcome [1]

MSNA

Timepoint [1]

Baseline visit

Eligibility

Key inclusion criteria

Case group 1 Inclusion Criteria
- A history of resistant hypertension, defined as the use of >=3 anti-hypertensive medications and failing to achieve blood pressure goals defined by a hypertensive specialist OR patients who achieve or do not achieve blood pressure goals on >=4 anti-hypertensive medications.
- Prevalent cardiovascular disease defined as a prior self-reported cerebrovascular disease event (stroke, transient ischemic attack), acute or chronic coronary syndrome, prior coronary revascularisation, or peripheral vascular disease. This will be self-reported and the diagnosis must be more than 6 months prior to screening.

Case group 2 Inclusion Criteria
- A history of essential hypertension, without resistant hypertension, and without a history of cardiovascular disease.
- Participants may or may not be using anti-hypertensive medications.

Healthy control group Inclusion Criteria
- No history of hypertension, nor cardiovascular disease. They will be taking no antihypertensive or antiarrhythmic medications.

Minimum age

40 Years

Maximum age

No limit

Sex

Both males and females

Healthy volunteers

Yes

Key exclusion criteria

Exclusion criteria
- Age <40 years old
- Currently pregnant or planning to be pregnant around the time of imaging. A pregnancy test will need to be undertaken by all female participants of childbearing age.
- chronic kidney disease (Stage 3 or higher, eGFR < 60ml/min/1.73m2) from a blood test performed within the 3 months prior to recruitment.
- BMI =35 kg/m2.
- History of heart failure with a reduced ejection fraction (known left ventricular ejection fraction <=50%)
- Severe mental health or stress related disorders requiring acute or urgent mental health care within the last 5 years, Stable, community-managed depression or generalised anxiety disorder treated by a primary care provider (e.g., GP) are not excluded. Use of a single antidepressant or anxiolytic medication does not meet exclusion criteria.
- History of recent or active malignancy (excluding non-melanoma skin cancer).
- Life expectancy <2 years as decided by investigator.
- Inability to provide written informed consent.
- Autonomic neuropathy or failure. In patients with diabetes, any known or self-reported neuropathy will be excluded.
- Hyper/hypothyroidism not currently being treated.
- Known primary hyperaldosteronism.
- Sleep apnoea prescribed CPAP or previously diagnosed sleep apnoea not using CPAP
- Recreational or regular use of illicit drugs, including sympathomimetics.
- Contra-indications to MRI imaging known at time of screening.
- Persistent atrial fibrillation.
- Permanent pacemaker inserted.

Study design

Purpose of the study

Diagnosis

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

The sample size is estimated based on our preliminary analyses (using AI contouring) that demonstrates a CG size of 1.31+/-0.43cm3 in people with a history of CVD, 1.10+/-0.41cm3 in people with hypertension, and 0.98+/-0.39cm3 in people without hypertension. However, because our analyses will be performed manually, we expect a lower standard deviation across groups (~0.25 cm3). With an alpha of 0.05, a power of 0.80, we anticipate that 36 total participants will be required to determine a significant difference in CG volume across three groups (n=12 each group). To allow for attrition, 15 participants in each group is planned.

Recruitment

Recruitment status

Not yet recruiting

Date of first participant enrolment

Anticipated

5/04/2027

Actual

Date of last participant enrolment

Anticipated

2/04/2029

Actual

Date of last data collection

Anticipated

7/05/2029

Actual

Sample size

Target

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

Recruitment hospital [1]

Royal Perth Hospital - Perth

Recruitment postcode(s) [1]

6000 - Perth

Funding & Sponsors

Funding source category [1]

Charities/Societies/Foundations

Name [1]

Royal Perth Hospital Medical Research Foundation

Address [1]

Country [1]

Australia

Primary sponsor type

Hospital

Name

Royal Perth Hospital

Address

Country

Australia

Secondary sponsor category [1]

None

Name [1]

Address [1]

Country [1]

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

WA Health Central HREC

Ethics committee address [1]

https://www.health.wa.gov.au/Articles/U_Z/WA-Health-Central-HREC

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

10/05/2026

Approval date [1]

12/08/2026

Ethics approval number [1]

Summary

Brief summary

Cardiovascular disease (CVD) remains a leading cause of death and there is a need to better understand modifiable risk factors, such as a dysfunctional autonomic nervous system (ANS). Preliminary data suggest there may be a difference in the size of the coeliac ganglia (CG) in people with prevalent hypertension and CVD, suggesting that CG size may be an indicator of a dysfunctional ANS. We propose that measuring the CG size by MRI imaging may be a non-invasive technique for understanding a person’s chronic exposure to a dysfunctional ANS. Furthermore, we propose that a molecular imaging technique, using Gallium-68 prostate-specific membrane antigen positron emission tomography (Ga-68 PSMA PET) imaging, can identify glutamate metabolism in the coeliac ganglia and may represent a real-time measure of ANS dysfunction. In this prospective case-control study, we are inviting three groups of people with differing levels of expected ANS dysfunction, to undergo MRI of the abdomen and Ga-68 PSMA PET/CT imaging.  Group 1 participants will have resistant hypertension and cardiovascular disease (n=15), group 2 participants essential hypertension (n=15) and group 3 are a control group with no hypertension and no cardiovascular disease (n=15). All participants will also undergo muscle sympathetic nerve activity (MSNA) testing as a gold standard of ANS dysfunction. The study will compare the size of the coeliac ganglia, and glutamate metabolism of the coeliac ganglia, across the three groups and with MSNA measures.

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

Dr Jamie Bellinge

Address

Department of Nuclear Medicine Sir Charles Gairdner Hospital Hospital Ave Nedlands WA 6009

Country

Australia

Phone

+61 8 6457 2179

Fax

[email protected]

Contact person for public queries

Name

Joanne Watts

Address

Department of Nuclear Medicine Sir Charles Gairdner Hospital Hospital Ave Nedlands WA 6009

Country

Australia

Phone

+61 8 6457 2179

Fax

[email protected]

Contact person for scientific queries

Name

Jamie Bellinge

Address

Department of Nuclear Medicine Sir Charles Gairdner Hospital Hospital Ave Nedlands WA 6009

Country

Australia

Phone

+61 8 6457 2179

Fax

[email protected]

Data sharing statement

Will the study consider sharing individual participant data?

Yes

Will there be any conditions when requesting access to individual participant data?

Persons/groups eligible to request access:
• Researchers
Conditions for requesting access:
• Yes, conditions apply:
• Requires review on a case-by-case basis by the trial custodian, sponsor or data sharing committee
• Requires a scientifically sound proposal or protocol
• Requires approval by an ethics committee
• Requires a data sharing agreement between data requester and trial custodian or sponsor

What individual participant data might be shared?

• All de-identified individual participant data

What types of analyses could be done with individual participant data?

• Any type of analysis (i.e. no restrictions on data re-use)

When can requests for individual participant data be made (start and end dates)?

From:
After publication of main results
To:
Not yet decided

Where can requests to access individual participant data be made, or data be obtained directly?

• Email of trial custodian, sponsor or committee: Emal of the research department; SCGH, Nuclear Medicine Research; [email protected]

Are there extra considerations when requesting access to individual participant 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.

Trial Review

Documents added manually

Documents added automatically