A CT echo triage model predicts markedly elevated pulmonary vascular resistance and right ventricular failure phenotype at catheterization
A Albulushi, A Tawfek, M Al-Sarmi, D De Silva, H Al-FarhanAbstract
Background
Identifying patients with markedly elevated pulmonary vascular resistance (PVR) before catheterization may improve prioritization, streamline testing, and anticipate RV failure risk.
Purpose
To evaluate whether a CT–echo model predicts high PVR and an invasive RV failure phenotype.
Methods
We included consecutive patients referred for PH evaluation undergoing contrast CT and echocardiography within 30 days of RHC (2021–2025). High PVR was defined as ≥5 Wood units. RV failure phenotype was defined as right atrial pressure ≥12 mmHg with cardiac index <2.2 L/min/m². CT markers included RV/LV ratio and PA/Ao ratio (Figure 1). Echo markers included TR velocity and TAPSE/PASP.
Results
Among 268 patients (mean age 53±16 years; 61% female), 71 (26%) had PVR ≥5 and 52 (19%) met RV failure phenotype (Table 1). High PVR was associated with higher RV/LV ratio (1.22±0.17 vs 0.97±0.16, p<0.001) and PA/Ao ratio (1.04±0.12 vs 0.91±0.10, p<0.001). Adding TAPSE/PASP improved prediction of RV failure phenotype (AUC 0.86 vs 0.79 with CT alone). A pragmatic rule (RV/LV ≥1.2 or PA/Ao ≥1.0 plus TAPSE/PASP <0.35) had 76% sensitivity and 78% specificity for RV failure phenotype and a negative predictive value of 92% (Figure 2).
Conclusion
A practical CT–echo triage model identifies patients likely to have markedly elevated PVR and invasive RV failure physiology, supporting earlier prioritization for catheterization and targeted management pathways.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.