RDW and RV-PA Coupling in Acute PE

Association Between Admission Red Cell Distribution Width and Right Ventricular-Pulmonary Arterial Coupling in Acute Pulmonary Embolism

Prior work linking RDW to echocardiographic findings in PE has largely focused on isolated parameters such as TAPSE or PASP and has rarely incorporated modern measures of RV-PA coupling. Whether admission RDW reflects the integrated RV-PA interaction - and not merely contractility or pressure in isolation - has not been adequately addressed. Establishing this link would support RDW as a simple, universally available marker of RV vulnerability at first presentation, and would lay the groundwork for future prognostic and mechanistic studies.

Study Overview

• Status: Not yet recruiting
• Conditions: Pulmonary Embolism Acute
• Intervention / Treatment: Other: Echo-cardiography

Detailed Description

Consecutive adults admitted via the emergency department or transferred to the participating center with confirmed acute PE will be screened by the study team.

1. Demographic and clinical

   • Age, sex, body mass index and Smoking status.
   • Comorbidities: hypertension, diabetes mellitus, coronary artery disease, heart failure, Chronic Obstructive Pulmonary Disease, chronic kidney disease, prior venous thromboembolism, active cancer, recent surgery, recent immobilization, history of COVID -19 infection and vaccination.
   • Current medications relevant to erythropoiesis or hemodynamics (ACE inhibitors/ARBs, beta-blockers, diuretics, iron supplementation, erythropoiesis-stimulating agents, anticoagulants on admission).

2. Laboratory

   • Complete blood count: hemoglobin, MCV, MCH, RDW-CV, RDW, white cell count and differential, platelet count, mean platelet volume.
   • Renal and hepatic function: creatinine, eGFR, AST, ALT, total bilirubin.
   • Cardiac biomarkers: high-sensitivity troponin. 3 Imaging
   • CTPA: anatomic location of thrombus (main, lobar, segmental, subsegmental), presence of saddle embolus, RV/LV diameter ratio on axial imaging.

4.Echocardiography

All echocardiograms will follow a standardized acquisition protocol based on the American Society of Echocardiography and European Association of Cardiovascular Imaging recommendations for RV assessment. Key elements:

• Left lateral decubitus position when tolerated; semi-recumbent if dyspneic.
• ECG-gated digital loops of at least three consecutive cardiac cycles for each view.
• Mandatory views: parasternal long-axis and short-axis; apical four-chamber, RV-focused four-chamber, two-chamber, and three-chamber; subcostal four-chamber and IVC.
• M-mode through the lateral tricuspid annulus for TAPSE.
• Continuous-wave Doppler across the tricuspid valve for peak TR velocity (multiple windows attempted; agitated saline contrast may be used to improve TR signal at operator discretion).
• Tissue Doppler at the lateral tricuspid annulus for S'.
• Speckle-tracking acquisition optimized for RV strain (frame rate 50-80 fps). Studies will be acquired on a single ultrasound platform (or ≤2 platforms with documented inter-platform agreement) and analyzed offline using vendor-neutral software where possible. Studies failing image-quality criteria for the primary outcome will be flagged and the participant excluded from the primary analysis

• Study Type: Observational
• Enrollment (Estimated): 190

Contacts and Locations

• Study Contact: Name: Entsar Hsanen Mohamed, lecturer; Phone Number: +201019968106; Email: entsar.hsanen@aun.edu.eg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adults, hemodynamically stable with acute pulmonary embolism

Description

Inclusion Criteria:

Age ≥ 18 years. Acute PE confirmed by computed tomography pulmonary angiogram (CTPA) performed within 24 h of presentation.

CBC obtained within 24 h of admission and before any blood transfusion. Transthoracic echocardiography feasible within 24 h of admission. Written informed consent.

Exclusion Criteria:

• Active hematologic malignancy or recent chemotherapy with myelosuppressive intent.
• Red blood cell transfusion within the preceding 90 days.
• Known hemoglobinopathy (e.g., sickle cell disease, thalassemia major).
• Chronic dialysis or eGFR < 15 mL/min/1.73 m².
• Pre-existing severe pulmonary hypertension (resting mean PAP ≥ 35 mmHg by prior right heart catheterization or echocardiographic PASP ≥ 60 mmHg before this admission), severe left-sided valvular disease, or known severe biventricular dysfunction.
• Hemodynamic instability requiring vasopressors at the time of echocardiography, as their hemodynamics may distort RV-PA coupling estimates.
• Inadequate echocardiographic image quality precluding measurement of TAPSE and a quantifiable TR jet for PASP estimation.
• Inability to provide informed consent.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Acute PE confirmed by computed tomography pulmonary angiogram (CTPA) performed within 24 h

Other: Echo-cardiography; All echocardiograms will follow a standardized acquisition protocol based on the American Society of Echocardiography and European Association of Cardiovascular Imaging recommendations for RV assessment. Key elements: Left lateral decubitus position when tolerated; semi-recumbent if dyspneic.; ECG-gated digital loops of at least three consecutive cardiac cycles for each view.; Mandatory views: parasternal long-axis and short-axis; apical four-chamber, RV-focused four-chamber, two-chamber, and three-chamber; subcostal four-chamber and IVC.; M-mode through the lateral tricuspid annulus for TAPSE.; Continuous-wave Doppler across the tricuspid valve for peak TR velocity (multiple windows attempted; agitated saline contrast may be used to improve TR signal at operator discretion).; Tissue Doppler at the lateral tricuspid annulus for S

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
assess the association between admission red cell distribution width (RDW) and right ventricular-pulmonary arterial coupling, measured by TAPSE/PASP ratio on transthoracic echocardiography performed within 24 hours of admission, in adults with acute PE	To assess the association between admission red cell distribution width (RDW) and right ventricular-pulmonary arterial coupling, measured by the TAPSE/PASP ratio on transthoracic echocardiography performed within 24 h of admission, in adults with acute pulmonary embolism	24 hours

Collaborators and Investigators

• Sponsor: Assiut University

Study record dates

Study Major Dates

• Study Start (Estimated): June 15, 2026
• Primary Completion (Estimated): June 15, 2027
• Study Completion (Estimated): December 15, 2027

Study Registration Dates

• First Submitted: May 21, 2026
• First Submitted That Met QC Criteria: May 27, 2026
• First Posted (Actual): June 1, 2026

Study Record Updates

• Last Update Posted (Actual): June 1, 2026
• Last Update Submitted That Met QC Criteria: May 27, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Embolism; RDW; Right Ventricular-Pulmonary Arterial Coupling
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Embolism and Thrombosis; Embolism
• Other Study ID Numbers: RDW and RV-PA Coupling in PE

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No