RDW and RV-PA Coupling in Acute PE

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.