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Trial details imported from

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Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
Investigating the Effects of Hyperoxia on Fractional Flow Reserve
Scientific title
Investigating the Effects of Hyperoxia on Fractional Flow Reserve in Patients With Moderate Coronary Artery Disease
Secondary ID [1] 0 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Coronary Artery Disease 0 0
Condition category
Condition code
Cardiovascular 0 0 0 0
Coronary heart disease
Cardiovascular 0 0 0 0
Other cardiovascular diseases
Respiratory 0 0 0 0
Other respiratory disorders / diseases

Study type
Description of intervention(s) / exposure
Treatment: Surgery - High Flow oxygen
Treatment: Surgery - Room Air

Experimental: High Flow oxygen - 10 minute of 10/L min of inhaled oxygen with reservoir bag.

Experimental: Room Air -

Treatment: Surgery: High Flow oxygen
10 minute shigh flow oxygen

Treatment: Surgery: Room Air
Room air breathing

Intervention code [1] 0 0
Treatment: Surgery
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Fractional flow reserve
Timepoint [1] 0 0
Duration of inpatient stay 2-3 days
Secondary outcome [1] 0 0
index of micro-vascular resistance
Timepoint [1] 0 0
Duration of inpatient stay 2-3 days

Key inclusion criteria
- Adults = 18 years of age, AND

- Undergoing elective coronary angiography

- Evidence of moderate (40%-79%) stenosis, requiring further routine assessment with
Minimum age
18 Years
Maximum age
90 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
- Acute coronary syndrome

- Hypoxia with oxygen saturation measured on pulse oximeter < 94% with the patient
breathing air

- Altered conscious state

- Evidence of left ventricular failure or cardiogenic shock

- Unable to perform consent prior to procedure

- Known hypersensitivity to adenosine

- Sick sinus syndrome, second or third degree atrioventricular (A-V) block (except in
patients with a functioning artificial pacemaker).

- Chronic Obstructive lung disease COPD or asthma

- Long QT syndrome

- Severe hypotension

- Concomitant use of dipyridamole

Study design
Purpose of the study
Basic Science
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
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Unknown status
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Alfred Hospital - Melbourne
Recruitment postcode(s) [1] 0 0
3004 - Melbourne

Funding & Sponsors
Primary sponsor type
Bayside Health

Ethics approval
Ethics application status

Brief summary
Coronary artery disease (CAD) is a condition which refers to the narrowing of the small blood
vessels that supplies blood and oxygen to the heart. It is a common cause of chest-pain
related symptoms and as a result of a 'heart attack'. In most cases, to assess the severity
of the disease is to use coronary angiography, which is a medical imaging technique that uses
contrast (a dye) and x-ray to show the blood-flow supply of the coronary arteries.

The optimal treatment for patients with symptomatic coronary disease is aggressive medical
therapy. Current guidelines recommend patients with symptomatic CAD and severe disease on
angiography undergo revascularisation therapy, which aims to restore blood flow to blocked
arteries. This can be done by either percutaneous coronary intervention (feeding a small
balloon or other device on a thin tube through blood vessels to the point of blockage and
then inflate the balloon to open the artery), or coronary artery bypass grafting (open-heart

For many symptomatic patients who have only moderate disease on angiography, further
functional testing is required to assess the extent of the blockage. This can be achieved by
placing a pressure wire to the artery of interest, to determine the likelihood that the
blockage impedes oxygen delivery to the heart muscle, known as the Fractional Flow Reserve
(FFR)3. FFR is commonly performed at the Alfred hospital in the assessment of such patients.
During an FFR procedure, further information regarding the health of the small arteries of
the heart can be obtained with the calculation of the index of micro-vascular resistance

Giving oxygen to patients with CAD is a common clinical practice, especially to all patients
in the catheterisation laboratory whose had a 'heart attack' and often administered
concurrently with light sedation during elective procedures.

Recently, however, the safety of routine supplemental oxygen in patients with CAD has been
questioned5. A research study analysed the outcomes of three small randomised studies on
oxygen in patients who experienced a 'heart attack', while suggestive of harm, the findings
of the study remain inconclusive.

There may also be deleterious effects of supplemental oxygen, on more stable patients with
CAD, who are not experiencing a 'heart attack'. Supplemental oxygen administered in the
catheterisation laboratory to patients with stable CAD, has been shown to significantly
reduce coronary artery blood flow and increase its resistance6-8. It has also been shown to
reduce cardiac output and effect the relaxation phase of the heart cycle. Based on this data
it is hypothesised that supplemental oxygen may affect FFR in patients with moderate CAD. The
investigators therefore propose to undertake a study of the effects of supplemental oxygen on
FFR in patients with moderate CAD.

The patients enrolled into the study will be scheduled for an elective normal contrast
diagnostic or interventional procedure as part of their clinically-indicated care. Once a
moderate blockage of the artery has been identified, FFR and IMR will be measured. During the
first phase of the FFR study, the patient will breathe room air and have a blood test to
measure their oxygen level (blood gas). There is a 3 minute washout period, followed by the
second phase, whereby the patient will be given 100% oxygen for 10 minutes and have another
blood gas measured.

The study will be conducted at Alfred Hospital with a total enrollment of 18 subjects. The
estimated time to complete enrollment is 6-10 months.

Data collected on each patient will include demographics, medical history, vital signs (heart
rate, blood pressure, height, and weight), usage of cardiovascular medications, pathology
results and procedural records. Any adverse events or serious adverse events related to the
study procedure will also be recorded.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
For IPD and results data, please see