Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000959471p
Ethics application status
Submitted, not yet approved
Date submitted
22/05/2025
Date registered
2/09/2025
Date last updated
2/09/2025
Date data sharing statement initially provided
2/09/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Hypertension: a modifiable risk factor in patients with aortic dissection.
Scientific title
Hypertension in Aortic Dissection
Secondary ID [1] 314396 0
Nil Known
Universal Trial Number (UTN)
U1111-1322-4301
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypertension 337402 0
Aortic Dissection Type A 337403 0
Aortic Dissection Type B 337406 0
Aortic Aneurysm 337407 0
Condition category
Condition code
Cardiovascular 333781 333781 0 0
Hypertension
Cardiovascular 333928 333928 0 0
Diseases of the vasculature and circulation including the lymphatic system

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
This observational study will consist of a 30-60 min screening visit, followed by a 2-3 hour experimental visit. Studies will be conducted in Human Cardiorespiratory Physiology Laboratory within the Clinical Research Centre, Faculty of Health and Medical Science, University of Auckland. The following physiological measures will be made in survivors of Type A and Type B dissection, patients with stable ascending aortic aneurysms and healthy control participants. All assessments will be one-on-one.
n=20 participants per group (total 80 participants).

Assessments:

Screening / familiarisation:
Obtain written informed consent.
Health Screening Questionnaires (Health screening questionnaire, EQ-5D-5L, IPAQ)
Virtual or in-person consult (30-60 min) conducted by a research nurse.

Experimental protocol - one experimental visit:
Conducted by a trained investigator.
The experimental visit will last ~2-3 hours.

Arterial stiffness
Measured by the placement of a pen-shaped probe over arteries at the participants neck, wrist, and ankle. A cuff will be placed around the participants upper thigh that will inflate for a couple of minutes.
Delivered by a trained investigator. Delivered face-to-face.
Delivered once. Takes 10-15 min to complete this assessment.

Flow mediated dilatation
While brachial artery is imaged with ultrasound a cuff around the upper arm will be inflated [for 5 minutes] and then deflated [5 minutes].
Delivered by a trained investigator. Delivered face-to-face.
Delivered once. Takes 10-15 min to complete this assessment.

Sympathetic nerve activity.
Sympathetic nerve activity recordings involve the insertion of a small, sterile wire (measuring 1-5 um) into the peroneal nerve near the fibular head.

Standardised cardiovascular tests will then be administered separated by a ~10 minute break. All measures will be delivered by a trained investigator. Delivered face-to-face. This will involve:
1) Resting baseline (10 min): Participant will rest quietly while physiological signals are recorded.
2) Slow deep breathing at 6 breaths/min (5 min): The participant will be asked to take slow deep breaths for 5 minutes with the guidance of an investigator.
3) Mental arithmetic: Paced auditory serial addition test (PASAT) (6 min): The participant will be required to add two sequentially presented single-digit numbers, while retaining the latter of the two numbers in their memory for subsequent addition to the next number presented.
4) Cold pressor test (2 min): The participant will be asked to place a hand in cold water for 2 minutes, followed by 2 minutes of recovery.
5) Handgrip (2 min): The participant will be asked to hold a device that measures the force of the handgrip. The participant will do some short handgrip trials to establish the maximum grip strength, then hold ~30% of this for 2 min
Intervention code [1] 331032 0
Not applicable
Comparator / control treatment
Age- and biological sex-matched normotensive controls aged 18 years old and above with no history of aortic disease (dissection or aneurysm or other exclusion criteria).

All participants will attend the study visit and associated testing. The control group will be used as the primary comparator in pairwise analyses across all measures.
Control group
Active

Outcomes
Primary outcome [1] 341418 0
24-hr blood pressure
Timepoint [1] 341418 0
Assessed over 24-hrs following laboratory visit 1
Primary outcome [2] 341419 0
Muscle sympathetic nerve activity.
Timepoint [2] 341419 0
Assessed continuously for ~1.5 hours during laboratory visit 1.
Primary outcome [3] 342330 0
Arterial stiffness
Timepoint [3] 342330 0
Assessed once at a single time-point during laboratory visit 1
Secondary outcome [1] 447987 0
Endothelial function
Timepoint [1] 447987 0
Assessed once at a single time-point during laboratory visit 1
Secondary outcome [2] 450805 0
Heart rate
Timepoint [2] 450805 0
Assessed continuously for ~1.5 hours during laboratory visit 1
Secondary outcome [3] 450806 0
Blood pressure
Timepoint [3] 450806 0
Assessed continuously for ~1.5 hours during laboratory visit 1
Secondary outcome [4] 451506 0
Blood pressure response to slow deep breathing
Timepoint [4] 451506 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [5] 451508 0
Blood pressure response to Paced Auditory Serial Addition Test
Timepoint [5] 451508 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [6] 451509 0
Blood pressure response to Cold Pressor Test
Timepoint [6] 451509 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [7] 451510 0
Blood pressure response to Handgrip test
Timepoint [7] 451510 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [8] 451511 0
Muscle sympathetic nerve activity response to Slow Deep Breathing.
Timepoint [8] 451511 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [9] 451512 0
Muscle sympathetic nerve activity response to Paced Auditory Serial Addition Test.
Timepoint [9] 451512 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [10] 451513 0
Muscle sympathetic nerve activity response to Cold Pressor Test.
Timepoint [10] 451513 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [11] 451514 0
Muscle sympathetic nerve activity response to Handgrip test.
Timepoint [11] 451514 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [12] 451515 0
Heart rate response to Slow Deep Breathing.
Timepoint [12] 451515 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [13] 451521 0
Heart rate response to Paced Auditory Serial Addition Test.
Timepoint [13] 451521 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [14] 451522 0
Heart rate response to Cold Pressor Test.
Timepoint [14] 451522 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.
Secondary outcome [15] 451523 0
Heart rate response to Handgrip test.
Timepoint [15] 451523 0
Assessed continuously for ~30 min during laboratory visit 1 cardiovascular tests.

Eligibility
Key inclusion criteria
• Participants with a clinical diagnosis of aortic dissection (type A or type B) or ascending aortic aneurysm
• Normotensive controls (office SBP < 120 mmHg and DBP < 80 mmHg) participants
• Men and women
• Aged over 18 years
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
• Severe untreated arterial hypertension at rest (>200 mmHg systolic, >120 mmHg diastolic)
• Significant pulmonary hypertension
• Unstable angina
• Abdominal aortic aneurysm >8.0 cm
• Active endocarditis, myocarditis or pericarditis
• Significant arterial desaturation at rest on room air <85%
• Severe aortic stenosis
• Severe aortic regurgitation
• History of connective tissue disorders (including Marfan’s, Loeys-Dietz, Ehlers-Danlos syndrome)
• History of coarctation of the aorta
• Upper limb arterio-venous fistulas
• Use of radial artery conduit
• Aortic arch surgery
• Upper limb amputation
• Significant arrhythmias (e.g., atrial fibrillation, previous VT / significant ventricular ectopy)
• Severe left ventricular dysfunction
• Recent (< 3 months) ischemic stroke
• Current smoker
• Body mass index < 18 kg/m2.
• Current pregnancy
• Users of recreational drugs
• Abusers of alcohol
• Inability to fully or appropriately provide consent (e.g., language issue, reading capability)
• Underlying medical conditions, which in the opinion of the Investigator place the participant at unacceptably high risk for participating in the study

Study design
Purpose
Screening
Duration
Cross-sectional
Selection
Defined population
Timing
Both
Statistical methods / analysis
Anthropometric (e.g., BMI) and demographic (e.g., age) information gathered at primary screening will be quantified using basic statistics (mean, SD, Median, IQR) and graphical presentations (boxplots, histograms, scatter plots). Likewise, levels of primary and secondary outcomes will be similarly reported. Resting values and the responses to physiological stressor tasks will be compared between groups. Normal distribution will be evaluated using Shapiro-Wilk tests. Comparisons of normally distributed physiological variables for a given trial will be made using a t-test, and non-normally distributed data evaluated using a Mann–Whitney U test. In the event of potential confounding differences in baseline characteristics (e.g., physical activity), analysis of covariance (ANCOVA) will be employed. Statistical analysis will be performed using SPSS (IBM Corp.,). Significance will be set at p < 0.05. Normally distributed data will be presented as mean (SD) while non-normally distributed data will be presented as median [interquartile range].

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/10/2025
Actual
Date of last participant enrolment
Anticipated
1/06/2027
Actual
Date of last data collection
Anticipated
1/07/2027
Actual
Sample size
Target
80
Accrual to date
Final
Recruitment outside Australia
Country [1] 27064 0
New Zealand
State/province [1] 27064 0
Waikato and Auckland regions

Funding & Sponsors
Funding source category [1] 318914 0
Charities/Societies/Foundations
Name [1] 318914 0
John and Ann Burton Award - Manaaki Manawa Centre for Heart Research
Country [1] 318914 0
New Zealand
Primary sponsor type
University
Name
The University of Auckland
Address
Country
New Zealand
Secondary sponsor category [1] 321483 0
Individual
Name [1] 321483 0
Dr Nishith Patel - A/Prof of Surgery, University of Auckland
Address [1] 321483 0
Country [1] 321483 0
New Zealand

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 317530 0
Auckland Health Research Ethics Committee
Ethics committee address [1] 317530 0
Ethics committee country [1] 317530 0
New Zealand
Date submitted for ethics approval [1] 317530 0
31/07/2025
Approval date [1] 317530 0
Ethics approval number [1] 317530 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 141342 0
A/Prof Nishith Patel
Address 141342 0
Department of Surgery, University of Auckland, Building 507, 20-33 Park Avenue, Grafton, Auckland 1023
Country 141342 0
New Zealand
Phone 141342 0
+64 0272421310
Fax 141342 0
Email 141342 0
[email protected]
Contact person for public queries
Name 141343 0
Nishith Patel
Address 141343 0
Department of Surgery, University of Auckland, Building 507, 20-33 Park Avenue, Grafton, Auckland 1023
Country 141343 0
New Zealand
Phone 141343 0
+64 0272421310
Fax 141343 0
Email 141343 0
[email protected]
Contact person for scientific queries
Name 141344 0
James Fisher
Address 141344 0
Department of Physiology, University of Auckland, 85 Park road, Grafton, Auckkland 1023
Country 141344 0
New Zealand
Phone 141344 0
+64 0225446014
Fax 141344 0
Email 141344 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No
No IPD sharing reason/comment: Individual data will not be provided for data protection and patient confidentiality reasons.



What supporting documents are/will be available?

TypeCitationLinkEmailOther DetailsAttachment
Informed consent form    PISCF - HyperAD v2 260625.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.