UMIN-ICDS Clinical Trial
| Unique ID issued by UMIN | UMIN000059461 |
|---|---|
| Receipt number | R000068007 |
| Scientific Title | Isovolumetric Relaxation Time as a Noninvasive Index of Pulmonary Vascular Resistance in Idiopathic Pulmonary Fibrosis |
| Date of disclosure of the study information | 2025/11/28 |
| Last modified on | 2025/11/28 08:04:57 |
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Basic information
Public title
Isovolumetric Relaxation Time and Pulmonary Vascular Resistance in Idiopathic Pulmonary Fibrosis: A Retrospective Single-Center Study
Acronym
IPF-IRT Study
Scientific Title
Isovolumetric Relaxation Time as a Noninvasive Index of Pulmonary Vascular Resistance in Idiopathic Pulmonary Fibrosis
Scientific Title:Acronym
IPF-IRT Study
Region
| Japan |
Condition
Condition
Idiopathic Pulmonary Fibrosis (IPF)
Classification by specialty
| Pneumology |
Classification by malignancy
Others
Genomic information
NO
Objectives
Narrative objectives1
The aim of this study is to determine whether right ventricular isovolumetric relaxation time (IRT) obtained by echocardiography can serve as a noninvasive indicator of pulmonary vascular resistance (PVR) measured by right heart catheterization in patients with idiopathic pulmonary fibrosis (IPF).
Basic objectives2
Others
Basic objectives -Others
Observational validation of diagnostic/physiologic association. To assess the extent to which echocardiographic isovolumetric relaxation time (IRT) reflects invasively measured pulmonary vascular resistance (PVR), focusing on continuous associations.
Trial characteristics_1
Exploratory
Trial characteristics_2
Others
Developmental phase
Not applicable
Assessment
Primary outcomes
The relationship between right ventricular isovolumetric relaxation time (IRT) and pulmonary vascular resistance (PVR).
The primary outcome is the strength of association (correlation coefficient and regression coefficient) between IRT and PVR.
The pulmonary vascular resistance index (PVRI), adjusted for body surface area, will also be analyzed as a supplementary parameter.
Key secondary outcomes
Relationships between hemodynamic parameters obtained from right heart catheterization (mPAP, PAWP, PVR, PVRI, etc.) and clinical indices including %DLCO, %FVC, 6-minute walk distance and mMRC.
Stepwise changes in IRT and related variables across pulmonary hypertension severity groups (No-PH, Borderline, PH), assessed by Spearman trend analysis.
Exploratory analyses of associations among other physiologic and clinical variables, as appropriate.
Base
Study type
Observational
Study design
Basic design
Randomization
Randomization unit
Blinding
Control
Stratification
Dynamic allocation
Institution consideration
Blocking
Concealment
Intervention
No. of arms
Purpose of intervention
Type of intervention
Interventions/Control_1
Interventions/Control_2
Interventions/Control_3
Interventions/Control_4
Interventions/Control_5
Interventions/Control_6
Interventions/Control_7
Interventions/Control_8
Interventions/Control_9
Interventions/Control_10
Eligibility
Age-lower limit
| 18 | years-old | <= |
Age-upper limit
| Not applicable |
Gender
Male and Female
Key inclusion criteria
Adults aged 18 years or older.
Diagnosed with idiopathic pulmonary fibrosis (IPF) by multidisciplinary discussion (MDD) according to ATS/ERS/JRS/ALAT criteria based on high-resolution computed tomography (HRCT) findings.
Underwent both right heart catheterization (RHC) and comprehensive transthoracic echocardiography within the same hospitalization, performed within 30 days (<=60 days allowable).
Evaluated under stable clinical conditions, defined as no acute exacerbation, respiratory infection, hospitalization, or steroid escalation within the preceding 4-8 weeks.
Availability of complete hemodynamic data (mPAP, PAWP, cardiac output) and analyzable Doppler waveforms for right ventricular isovolumetric relaxation time (IRT) and pulmonary artery acceleration time (PAAcT).
Patients receiving antifibrotic therapy (pirfenidone or nintedanib) were eligible if treatment had been stable for at least four weeks prior to evaluation.
Patients with combined pulmonary fibrosis and emphysema (CPFE) were excluded; however, limited paraseptal or centrilobular emphysema involving less than 10 percent of the total lung field was acceptable.
Key exclusion criteria
Presence of left-sided heart disease (left ventricular ejection fraction <50%, moderate-to-severe valvular disease, or hypertrophic/restrictive cardiomyopathy).
Pulmonary artery wedge pressure (PAWP) >15 mmHg.
Combined pulmonary fibrosis and emphysema (CPFE) as determined by two pulmonologists and one radiologist, defined as upper-lobe predominant emphysema coexisting with lower-lobe predominant fibrosis on HRCT.
Chronic thromboembolic pulmonary hypertension confirmed by CT pulmonary angiography or ventilation-perfusion (V/Q) scanning.
Non-IPF interstitial lung diseases, including connective tissue disease-associated ILD, hypersensitivity pneumonitis, or sarcoidosis.
Atrial fibrillation or other significant arrhythmias interfering with accurate time-interval measurements.
Poor echocardiographic image quality precluding reliable Doppler waveform analysis.
Missing key hemodynamic or echocardiographic data (mPAP, PAWP, cardiac output, IRT, PAAcT, etc.).
Patients who had initiated pulmonary arterial hypertension-specific therapy prior to RHC or echocardiographic evaluation.
Patients with acute exacerbation, respiratory infection, or clinically unstable condition at the time of evaluation.
Target sample size
121
Research contact person
Name of lead principal investigator
| 1st name | Yosuke |
| Middle name | |
| Last name | Tanaka |
Organization
Nippon Medical School Hospital
Division name
Department of Respiratory Medicine
Zip code
113-8603
Address
1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
TEL
03-3822-2131
yosuke-t@nms.ac.jp
Public contact
Name of contact person
| 1st name | Yosuke |
| Middle name | |
| Last name | Tanaka |
Organization
Nippon Medical School Hospital
Division name
Department of Respiratory Medicine
Zip code
113-8603
Address
1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
TEL
13-3822-2131
Homepage URL
yosuke-t@nms.ac.jp
Sponsor or person
Institute
Nippon Medical School
Institute
Department
Personal name
Yosuke Tanaka
Funding Source
Organization
Nippon Medical School
Organization
Division
Category of Funding Organization
Self funding
Nationality of Funding Organization
Other related organizations
Co-sponsor
Name of secondary funder(s)
IRB Contact (For public release)
Organization
Institutional Review Board of Nippon Medical School Hospital
Address
1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan
Tel
03-3822-2131
nms_fuzokurinri@nms.ac.jp
Secondary IDs
Secondary IDs
NO
Study ID_1
Org. issuing International ID_1
Study ID_2
Org. issuing International ID_2
IND to MHLW
Institutions
Institutions
日本医科大学付属病院
Other administrative information
Date of disclosure of the study information
| 2025 | Year | 11 | Month | 28 | Day |
Related information
URL releasing protocol
Publication of results
Unpublished
Result
URL related to results and publications
Number of participants that the trial has enrolled
121
Results
Results date posted
Results Delayed
Results Delay Reason
Date of the first journal publication of results
Baseline Characteristics
Participant flow
Adverse events
Outcome measures
Plan to share IPD
IPD sharing Plan description
Progress
Recruitment status
No longer recruiting
Date of protocol fixation
| 2020 | Year | 10 | Month | 01 | Day |
Date of IRB
| 2025 | Year | 10 | Month | 01 | Day |
Anticipated trial start date
| 2020 | Year | 10 | Month | 01 | Day |
Last follow-up date
| 2025 | Year | 10 | Month | 31 | Day |
Date of closure to data entry
| 2025 | Year | 11 | Month | 30 | Day |
Date trial data considered complete
| 2025 | Year | 12 | Month | 15 | Day |
Date analysis concluded
| 2026 | Year | 01 | Month | 31 | Day |
Other
Other related information
This study is a single-center, retrospective observational study conducted at Nippon Medical School Hospital, including patients who underwent right heart catheterization and echocardiography between October 2020 and October 2025. No new interventions or patient recruitment were performed; anonymized existing clinical data were analyzed. The study was conducted under the comprehensive ethical approval of the Institutional Review Board of Nippon Medical School Hospital, with individual consent waived by the opt-out policy. The results are intended for submission to AJRCCM
Although the study protocol was finalized in October 2025, the protocol fixation date was set to October 1, 2020, for consistency within the UMIN registration system, as this is a retrospective study.
Management information
Registered date
| 2025 | Year | 10 | Month | 19 | Day |
Last modified on
| 2025 | Year | 11 | Month | 28 | Day |
Link to view the page
Value
https://center6.umin.ac.jp/cgi-open-bin/icdr_e/ctr_view.cgi?recptno=R000068007
