Noninvasive Assessment of Pulmonary Vascular Resistance Using Right-Ventricular IRT in Idiopathic Pulmonary Fibrosis

Retrospective Observational Study on the Association Between Right-Ventricular Isovolumetric Relaxation Time and Pulmonary Vascular Resistance in Idiopathic Pulmonary Fibrosis - IPF-IRT Study

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

JPRN

Registry ID

JPRN-UMIN000059984

Enrollment

180

Registered

2026-01-10

Start date

2015-04-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Idiopathic Pulmonary Fibrosis

Interventions

None listed

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Age >= 20 years Diagnosis of idiopathic pulmonary fibrosis (IPF) based on ATS/ERS/JRS/ALAT guidelines Transthoracic echocardiography and right heart catheterization performed during the same hospitalization under stable conditions No acute exacerbation, infection, hospitalization, or corticosteroid escalation within the previous 4 to 8 weeks Antifibrotic therapy, if used, must be stable for at least 4 weeks before evaluation Complete hemodynamic data including mPAP, PAWP, and cardiac output Doppler waveforms for IRT and PAAT that are suitable for analysis CPFE cases are excluded (mild emphysema <10 percent is allowed) In addition, Patients receiving guideline-based long-term oxygen therapy (LTOT) at the minimum required flow for IPF-related hypoxemia and/or low-dose diuretics for congestion related to IPF-associated pulmonary hypertension were eligible, provided that these treatments had been stable for at least 4 weeks before the index hospitalization.

Exclusion criteria

Exclusion criteria: Left heart disease (LVEF < 50 percent, moderate or greater valvular disease, hypertrophic or restrictive cardiomyopathy) PAWP > 15 mmHg Interstitial lung diseases other than IPF Chronic thromboembolic disease confirmed by CT pulmonary angiography or ventilation perfusion scanning Atrial fibrillation or significant arrhythmias Acoustic windows inadequate for Doppler evaluation Use of pulmonary hypertension targeted therapy before echocardiography or right heart catheterization Missing essential echocardiographic or hemodynamic data

Design outcomes

Primary

Measure	Time frame
Correlation coefficient between isovolumetric relaxation time (IRT) and pulmonary vascular resistance index (PVRI) obtained from transthoracic echocardiography and right heart catheterization performed during the same hospitalization period.	—

Secondary

Measure	Time frame
Correlation between IRT and pulmonary vascular resistance (PVR). Correlation between IRT and mean pulmonary arterial pressure (mPAP). Association between IRT and right ventricular-pulmonary arterial coupling indices (e.g., TAPSE/sPAP). Comparison of IRT between patients with pulmonary hypertension (PH) and those without PH. Correlation between pulmonary artery acceleration time (PAAcT) and PVRI. Correlation of pulmonary function parameters (FVC, DLCO) with PVR and PVRI.	—

Measure

Time frame

Correlation between IRT and pulmonary vascular resistance (PVR). Correlation between IRT and mean pulmonary arterial pressure (mPAP). Association between IRT and right ventricular-pulmonary arterial coupling indices (e.g., TAPSE/sPAP). Comparison of IRT between patients with pulmonary hypertension (PH) and those without PH. Correlation between pulmonary artery acceleration time (PAAcT) and PVRI. Correlation of pulmonary function parameters (FVC, DLCO) with PVR and PVRI.

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Countries

Japan

Contacts

Public ContactYosuke Tanaka

Nippon Medical School Hospital Department of Respiratory Medicine

yosuke-t@nms.ac.jp03-3822-2131

Outcome results