Isovolumetric Relaxation Time and Pulmonary Vascular Resistance in Chronic Obstructive Pulmonary Disease (COPD): A Retrospective Single-Center Study

Isovolumetric Relaxation Time as a Noninvasive Index of Pulmonary Vascular Resistance in Chronic Obstructive Pulmonary Disease (COPD) - IPF-IRT Study

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

JPRN

Registry ID

JPRN-UMIN000059571

Enrollment

Registered

2025-10-31

Start date

2021-04-01

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

Chronic Obstructive Pulmonary Disease (COPD)

Interventions

None listed

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Adults aged between 20 and 80 years. Patients diagnosed with chronic obstructive pulmonary disease (COPD) by respiratory specialists according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. Clinically stable condition for at least 3 months, with no need for treatment modification. Underwent both echocardiographic and right heart catheterization (RHC) examinations for the evaluation of exertional dyspnea. Complete and analyzable clinical, echocardiographic, and hemodynamic data available.

Exclusion criteria

Exclusion criteria: Presence of diseases other than COPD that may cause pulmonary hypertension such as interstitial lung disease or chronic thromboembolic pulmonary hypertension. Left sided heart disease including left ventricular ejection fraction <50 percent or moderate to severe valvular heart disease. Presence of systemic inflammatory disorders or severe hepatic or renal dysfunction. Current use of medications that significantly affect hemodynamics such as systemic vasodilators or calcium channel blockers. Diagnosis of asthma or presence of a bronchodilator response to 400 micrograms of salbutamol with an increase in FEV1 >=200 mL. Incomplete data or missing parameters required for analysis. Inability to participate due to severe mental disorders or other conditions judged by investigators.

Design outcomes

Primary

Measure	Time frame
Association between right ventricular isovolumetric relaxation time (IRT) measured by echocardiography and pulmonary vascular resistance index (PVRI) measured by right heart catheterization. The strength of the association will be evaluated using correlation coefficients (Pearson or Spearman) and linear regression analysis.	—

Secondary

Measure	Time frame
Association between IRT and unindexed pulmonary vascular resistance (PVR). Association between IRT and clinical parameters, including mMRC dyspnea score, 6-minute walk distance (6MWD), and treadmill exercise test (TMET) performance. Correlation between PVRI and %FEV1, %DLCO, and mean pulmonary arterial pressure (mPAP). Comparison of echocardiographic parameters (IRT, PAAcT, TEI index) between COPD patients with and without pulmonary hypertension. Correlation between IRT and pulmonary function parameters (%DLCO, %FEV1). Association between IRT and hemodynamic variables obtained from right heart catheterization (mPAP, PAWP, CI, SvO2). Comparison of IRT values between patients with and without pulmonary hypertension (PH).	—

Measure

Time frame

Association between IRT and unindexed pulmonary vascular resistance (PVR). Association between IRT and clinical parameters, including mMRC dyspnea score, 6-minute walk distance (6MWD), and treadmill exercise test (TMET) performance. Correlation between PVRI and %FEV1, %DLCO, and mean pulmonary arterial pressure (mPAP). Comparison of echocardiographic parameters (IRT, PAAcT, TEI index) between COPD patients with and without pulmonary hypertension. Correlation between IRT and pulmonary function parameters (%DLCO, %FEV1). Association between IRT and hemodynamic variables obtained from right heart catheterization (mPAP, PAWP, CI, SvO2). Comparison of IRT values between patients with and without pulmonary hypertension (PH).

—

Countries

Japan

Contacts

Public ContactYosuke Tanaka

Nippon Medical School Hospital Department of Respiratory Medicine

yosuke-t@nms.ac.jp13-3822-2131

Outcome results