A novel right ventricular morphofunctional index integrating geometry and RV pulmonary arterial coupling for risk stratification in heart failure
D Inan, L A L E Dinc Asarcikli, S E L D A Murat, I N C I Colluoglu, N I J A T Bakhshaliyev, Z E Y N E P Ulutas, G I Z E M Cabuk, S E N E M Hasirci, A H M E T Celik, T O L G A Sinan GuvencAbstract
Background/Introduction
Right ventricular (RV) structure and function are key determinants of prognosis in heart failure (HF). Conventional echocardiographic indices such as tricuspid annular plane systolic excursion (TAPSE), RV fractional area change, tissue Doppler S′ velocity and, more recently, RV longitudinal strain and the TAPSE/systolic pulmonary artery pressure (sPAP) ratio are widely used to assess RV performance and RV–pulmonary arterial coupling. However, these parameters predominantly capture either geometric or functional aspects of the RV and may be influenced by loading conditions, image quality and complex RV anatomy, which may limit their reproducible prognostic value in clinical practice. Therefore, there is an unmet need for simple, integrative indices that combine RV morphology and function to better predict outcomes in HF.
Purpose
We aimed to investigate the prognostic value of a novel Right Ventricular Morphofunctional Index (RV-MFI) in predicting long-term mortality or HF-related hospitalization.
Methods
This retrospective observational study included 148 consecutive HF patients who presented to the cardiology outpatient clinic and underwent comprehensive transthoracic echocardiography. RV-MFI was calculated as (RV free-wall thickness / RV basal diameter) divided by (TAPSE / sPAP). The primary outcome was a composite of all-cause mortality or HF-related hospitalization at 12 months. Patients were categorized according to outcome status, and logistic regression analyses were performed.
Results
The composite outcome occurred in 36 patients (24.3%). Compared with event-free patients, those with adverse outcomes more frequently had male sex and higher NYHA class, and demonstrated greater cardiac remodeling, including larger LV volumes and higher left atrial volume index. RV geometry and function were also more impaired, with larger RV basal diameter, lower TAPSE and RV S′ velocity, larger right atrial area and higher sPAP. RV-MFI was significantly higher in the adverse-outcome group (0.50 ± 0.40 vs. 0.30 ± 0.20, p<0.001). In univariate analysis, higher RV-MFI was strongly associated with the primary outcome (OR 3.47, 95% CI 1.81–6.66; p<0.001). This association remained independent after adjustment for clinical and echocardiographic covariates (adjusted OR 4.07, 95% CI 1.66–9.97; p=0.002) (Table 1). Receiver-operating-characteristic analysis showed good discriminatory performance, and Kaplan–Meier analysis demonstrated significantly lower event-free survival with higher RV-MFI values (log-rank p<0.001) (Figure 1–2).
Conclusion
RV-MFI, a novel index integrating RV structural remodeling and RV–pulmonary arterial coupling, is independently associated with 12-month mortality or HF hospitalization and may support improved risk stratification.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.