Pulmonary HypertensionNCT05843461
PIMR and Pulmonary Vascular Disease
An observational study of Pulmonary Hypertension, run by University of California, Los Angeles at 1 site in United States.
Trial summary
The findings from this innovative, first-in-man, prospective pilot study will elucidate the role of PIMR and RV-IMR in pre-capillary PH. The study cohort will consist of patients with pulmonary pressures ranging from normal (advanced lung disease patients undergoing lung transplant evaluation) to severe PH (PAH and… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Pulmonary Hypertension
- What is being tested?
- Pulmonary Index of Microcirculatory Resistance, Right Ventricle Index of Microcirculatory Resistance and Pulmonary artery OCT
- How many people
- 30 participants
- Where
- 1 siteUnited States
- Study dates
- 10 Jan 2023to 31 Jul 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients scheduled to undergo standard-of-care right and left heart catheterization either for evaluation of suspected or known pulmonary hypertension (PAH or CTEPH) or for lung transplant evaluation in the setting of advanced lung disease
Who may be able to join
- ≥18 years old
- Able to provide informed written consent.
- Patients with 1) advanced lung disease requiring standard-of-care bilateral heart catheterization as part of lung transplant evaluation in whom mPAP < 20 mmHg on RHC, or 2) PAH/CTEPH (i.e. pre-capillary PH) undergoing standard-of-care bilateral heart catheterization as part of their work-up/treatment
Who cannot join
- Contraindicated to undergo fluoroscopy and/or coronary angiography (e.g. pregnancy)
- Chronic kidney disease (serum creatinine ≥ 2.0 mg/dL)
Trial locations and contacts
1 site in 1 country.
United States1 site
Ronald Reagan UCLA Medical Center
Los Angeles, California, 90095
About this study
Official title: The Pulmonary Index of Microcirculatory Resistance: a Novel Hemodynamic Index for Invasively Assessing the Pulmonary Vasculature
The findings from this innovative, first-in-man, prospective pilot study will elucidate the role of PIMR and RV-IMR in pre-capillary PH. The study cohort will consist of patients with pulmonary pressures ranging from normal (advanced lung disease patients undergoing lung transplant evaluation) to severe PH (PAH and CTEPH patients), and thus will allow for identification of a PIMR cutoff. Participants will include: 1) advanced lung disease patients undergoing bilateral heart catheterization as part of their pre-lung transplant work-up, and 2) newly referred patients to PAH and CTEPH clinics undergoing bilateral heart catheterization as part of standard of care work-up. All participants will undergo PIMR testing, and those with pre-capillary PH will also undergo pulmonary OCT and measurement of RV-IMR. The study seeks to define the relationship between PIMR and PH and to establish the PIMR threshold that identifies pulmonary microvascular dysfunction as well as to evaluate the association of PIMR and pulmonary vascular remodeling on OCT in patients with pre-capillary PH. In addition, the study will assess the relationship between RV-IMR and RV pressure overload among patients with pre-capillary PH.
- Conditions
- Pulmonary Hypertension
- Being tested
- Pulmonary Index of Microcirculatory Resistance, Right Ventricle Index of Microcirculatory Resistance, Pulmonary artery OCT
- Keywords
- Pulmonary Hypertension, Pulmonary Arterial Hypertension, Index of Microcirculatory Resistance, Chronic Thromboembolic Disease, Pulmonary Index of Microcirculatory Resistance
- Medical subject headings
- Hypertension, Pulmonary, Pulmonary Arterial Hypertension
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Pulmonary Index of Microcirculatory ResistanceOther
Also called PIMR
PIMR measurement involves placing a coronary pressure wire in the pulmonary arteries and making pressure/time measurements during maximal flow down the artery. PIMR of the right and left pulmonary arteries will be obtained.
Right Ventricle Index of Microcirculatory ResistanceOther
Also called RV-IMR
RV-IMR measurement involves placing a coronary pressure wire in the acute marginal branch of the right coronary artery and making pressure/time measurements during maximal flow down the artery.
Pulmonary artery OCTOther
OCT of the pulmonary artery involves advancing an OCT catheter over the pressure wire to image the pulmonary artery. OCT of the right and left pulmonary arteries will be performed.
| Study group | Role | What they receive |
|---|---|---|
| Controls | 10 patients without pulmonary hypertension (mean PA pressure less than 20 mmHg on RHC) Receives: Other: Pulmonary Index of Microcirculatory Resistance | |
| PAH | 10 patients with PAH Receives: Other: Pulmonary Index of Microcirculatory Resistance; Other: Right Ventricle Index of Microcirculatory Resistance; Other: Pulmonary artery OCT | |
| CTEPH | 10 patients with CTEPH Receives: Other: Pulmonary Index of Microcirculatory Resistance; Other: Right Ventricle Index of Microcirculatory Resistance; Other: Pulmonary artery OCT |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pulmonary Index of Microcirculatory Resistance (PIMR)
PressureWire advanced to distal third of segmental pulmonary artery (PA) for measurement of pulmonary hemodynamics. The derivation of IMR involves the application of Ohm's law (V=IR) to the coronary microcirculatory circuit, where the relationship between resistance (R) = IMR, voltage (V) = pressure (P), and current (I) = flow (Q) can be expressed as follows: IMR = ∆P/Q. ∆P = the change in pressure across the microvasculature (mean distal coronary artery pressure [Pd] - coronary venous pressure (Pv); Pv is typically disregarded because it is negligible relative to Pd. Based on the principles of thermodilution, flow is inversely proportion to mean transit time (Q ~ 1/Tmn). Lastly, the minimal achievable resistance occurs during maximal hyperemic flow when all available microvessels have theoretically been recruited. Hence, the calculation of IMR simplifies to the following formula: IMR = Pd (pulmonary artery) x TmnHyp.
Measured: Baseline
Right Ventricle Index of Microcirculatory Resistance (RV-IMR)
PressureWire advanced to distal third of acute marginal branch of the right coronary artery (RCA) for measurement of pulmonary hemodynamics. The derivation of IMR involves the application of Ohm's law (V=IR) to the coronary microcirculatory circuit, where the relationship between resistance (R) = IMR, voltage (V) = pressure (P), and current (I) = flow (Q) can be expressed as follows: IMR = ∆P/Q. ∆P = the change in pressure across the microvasculature (mean distal coronary artery pressure [Pd] - coronary venous pressure (Pv); Pv is typically disregarded because it is negligible relative to Pd. Based on the principles of thermodilution, flow is inversely proportion to mean transit time (Q ~ 1/Tmn). Lastly, the minimal achievable resistance occurs during maximal hyperemic flow when all available microvessels have theoretically been recruited. Hence, the calculation of IMR simplifies to the following formula: IMR = Pd (RCA marginal branch) x TmnHyp.
Measured: Baseline
OCT-derived pulmonary artery wall thickness
A Dragonfly Optis OCT catheter (Abbott) will be advanced over the PressureWireX to the distal left lower lobe segmental pulmonary artery (luminal diameter < 5 mm and minimal length of 50 mm). OCT images of the pulmonary artery will be recorded via automatic pullback and analyzed offline in a blinded manner.
Measured: Baseline
OCT-derived thickness-diameter ratio
A Dragonfly Optis OCT catheter (Abbott) will be advanced over the PressureWireX to the distal left lower lobe segmental pulmonary artery (luminal diameter < 5 mm and minimal length of 50 mm). OCT images of the pulmonary artery will be recorded via automatic pullback and analyzed offline in a blinded manner.
Measured: Baseline
OCT-derived wall-area ratio
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 May 2023
- Study start10 Jan 2023
- Primary completion31 Jul 2024
- Study completion31 Jul 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Pulmonary HypertensionStudies of the same condition, open and under way.
- More trials run by University of California, Los AngelesThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of California, Los Angeles
- Sponsor type
- University, hospital or other
- Collaborators
- Abbott
- Responsible party
- Principal investigator, Rushi V. Parikh, University of California, Los Angeles
- Investigators
- Rushi Parikh, MD, Principal investigator, University of California, Los Angeles
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05843461
- Sponsor's protocol ID
- IRB#22-001643
- Status last verified
- Dec 2024
- First submitted
- 24 Apr 2023
- Last updated
- 5 Dec 2024
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Dec 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Pulmonary Index of Microcirculatory Resistance: a Novel Hemodynamic Index for Invasively Assessing the Pulmonary Vasculature
- ClinicalTrials.gov ID
- NCT05843461
- Acronym / sponsor ID
- IRB#22-001643
- Conditions
- Pulmonary Hypertension
- Keywords
- Pulmonary Hypertension, Pulmonary Arterial Hypertension, Index of Microcirculatory Resistance, Chronic Thromboembolic Disease, Pulmonary Index of Microcirculatory Resistance
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 30 participants (actual)
- Lead sponsor
- University of California, Los AngelesUniversity, hospital or other
- Collaborators
- Abbott
- Study start
- 10 Jan 2023 (actual)
- Primary completion
- 31 Jul 2024 (actual)
- Study completion
- 31 Jul 2024 (actual)
- First posted
- 6 May 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The findings from this innovative, first-in-man, prospective pilot study will elucidate the role of PIMR and RV-IMR in pre-capillary PH. The study cohort will consist of patients with pulmonary pressures ranging from normal (advanced lung disease patients undergoing lung transplant evaluation) to severe PH (PAH and CTEPH patients), and thus will allow for identification of a PIMR cutoff. Participants will include: 1) advanced lung disease patients undergoing bilateral heart catheterization as part of their pre-lung transplant work-up, and 2) newly referred patients to PAH and CTEPH clinics undergoing bilateral heart catheterization as part of standard of care work-up. All participants will undergo PIMR testing, and those with pre-capillary PH will also undergo pulmonary OCT and measurement of RV-IMR. The study seeks to define the relationship between PIMR and PH and to establish the PIMR threshold that identifies pulmonary microvascular dysfunction as well as to evaluate the association of PIMR and pulmonary vascular remodeling on OCT in patients with pre-capillary PH. In addition, the study will assess the relationship between RV-IMR and RV pressure overload among patients with pre-capillary PH.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Controls | – | Other: Pulmonary Index of Microcirculatory Resistance10 patients without pulmonary hypertension (mean PA pressure less than 20 mmHg on RHC) |
| PAH | – | Other: Pulmonary Index of Microcirculatory Resistance, Other: Right Ventricle Index of Microcirculatory Resistance, Other: Pulmonary artery OCT10 patients with PAH |
| CTEPH | – | Other: Pulmonary Index of Microcirculatory Resistance, Other: Right Ventricle Index of Microcirculatory Resistance, Other: Pulmonary artery OCT10 patients with CTEPH |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients scheduled to undergo standard-of-care right and left heart catheterization either for evaluation of suspected or known pulmonary hypertension (PAH or CTEPH) or for lung transplant evaluation in the setting of advanced lung disease
Key inclusion criteria (3 listed)
- ≥18 years old
- Able to provide informed written consent.
- Patients with 1) advanced lung disease requiring standard-of-care bilateral heart catheterization as part of lung transplant evaluation in whom mPAP < 20 mmHg on RHC, or 2) PAH/CTEPH (i.e. pre-capillary PH) undergoing standard-of-care bilateral heart catheterization as part of their work-up/treatment
Key exclusion criteria (2 listed)
- Contraindicated to undergo fluoroscopy and/or coronary angiography (e.g. pregnancy)
- Chronic kidney disease (serum creatinine ≥ 2.0 mg/dL)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Pulmonary Index of Microcirculatory ResistanceAlso: PIMRPIMR measurement involves placing a coronary pressure wire in the pulmonary arteries and making pressure/time measurements during maximal flow down the artery. PIMR of the right and left pulmonary arteries will be obtained. | Other | CTEPH, Controls, PAH |
| Right Ventricle Index of Microcirculatory ResistanceAlso: RV-IMRRV-IMR measurement involves placing a coronary pressure wire in the acute marginal branch of the right coronary artery and making pressure/time measurements during maximal flow down the artery. | Other | CTEPH, PAH |
| Pulmonary artery OCTOCT of the pulmonary artery involves advancing an OCT catheter over the pressure wire to image the pulmonary artery. OCT of the right and left pulmonary arteries will be performed. | Other | CTEPH, PAH |
Primary outcome
Pulmonary Index of Microcirculatory Resistance (PIMR)
Time frame: Baseline
PressureWire advanced to distal third of segmental pulmonary artery (PA) for measurement of pulmonary hemodynamics. The derivation of IMR involves the application of Ohm's law (V=IR) to the coronary microcirculatory circuit, where the relationship between resistance (R) = IMR, voltage (V) = pressure (P), and current (I) = flow (Q) can be expressed as follows: IMR = ∆P/Q. ∆P = the change in pressure across the microvasculature (mean distal coronary artery pressure [Pd] - coronary venous pressure (Pv); Pv is typically disregarded because it is negligible relative to Pd. Based on the principles of thermodilution, flow is inversely proportion to mean transit time (Q ~ 1/Tmn). Lastly, the minimal achievable resistance occurs during maximal hyperemic flow when all available microvessels have theoretically been recruited. Hence, the calculation of IMR simplifies to the following formula: IMR = Pd (pulmonary artery) x TmnHyp.
Right Ventricle Index of Microcirculatory Resistance (RV-IMR)
Time frame: Baseline
PressureWire advanced to distal third of acute marginal branch of the right coronary artery (RCA) for measurement of pulmonary hemodynamics. The derivation of IMR involves the application of Ohm's law (V=IR) to the coronary microcirculatory circuit, where the relationship between resistance (R) = IMR, voltage (V) = pressure (P), and current (I) = flow (Q) can be expressed as follows: IMR = ∆P/Q. ∆P = the change in pressure across the microvasculature (mean distal coronary artery pressure [Pd] - coronary venous pressure (Pv); Pv is typically disregarded because it is negligible relative to Pd. Based on the principles of thermodilution, flow is inversely proportion to mean transit time (Q ~ 1/Tmn). Lastly, the minimal achievable resistance occurs during maximal hyperemic flow when all available microvessels have theoretically been recruited. Hence, the calculation of IMR simplifies to the following formula: IMR = Pd (RCA marginal branch) x TmnHyp.
OCT-derived pulmonary artery wall thickness
Time frame: Baseline
A Dragonfly Optis OCT catheter (Abbott) will be advanced over the PressureWireX to the distal left lower lobe segmental pulmonary artery (luminal diameter < 5 mm and minimal length of 50 mm). OCT images of the pulmonary artery will be recorded via automatic pullback and analyzed offline in a blinded manner.
OCT-derived thickness-diameter ratio
Time frame: Baseline
A Dragonfly Optis OCT catheter (Abbott) will be advanced over the PressureWireX to the distal left lower lobe segmental pulmonary artery (luminal diameter < 5 mm and minimal length of 50 mm). OCT images of the pulmonary artery will be recorded via automatic pullback and analyzed offline in a blinded manner.
OCT-derived wall-area ratio
Time frame: Baseline
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Dec 2024.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Rushi Parikh, MD principal investigator
University of California, Los Angeles
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Pulmonary Hypertension, run by University of California, Los Angeles at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 5 Dec 2024. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Pulmonary Index of Microcirculatory Resistance (PIMR) (time frame: Baseline). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Dec 2024.