Beyond clinical risk scores in pulmonary arterial hypertension: does invasive hemodynamic assessment provide additional value?

Background

Accurate risk stratification in pulmonary arterial hypertension (PAH) is essential for prognosis and treatment selection. Current multiparametric scores, such as REVEAL Lite and COMPERA, rely predominantly on clinical and biochemical variables, without incorporating invasive hemodynamic markers that are known strong predictors of outcome.

Purpose

To determine whether invasive hemodynamic variables provide incremental prognostic value beyond established clinical risk scores in PAH.

Methods

We prospectively followed 78 PAH patients (pts) for 12 months in a referral center. The composite endpoint included death, lung transplantation, initiation of intravenous prostanoids, or unscheduled hospitalization. Baseline right-heart catheterization was performed according to current guidelines. Prognostic associations were assessed using Cox models, and survival distributions were compared with Kaplan–Meier analysis.

Results

Mean age at diagnosis was 52.3 ± 17.2 years, and 69.2% were female (n=54). WHO functional class III–IV was present in 79.5% of pts. Fourteen pts (18%) reached the composite endpoint.

In univariate analysis, REVEAL Lite (HR 1.56, p=0.004) and COMPERA (HR 4.97, p=0.003) were significantly associated with adverse outcomes. Among hemodynamic variables, right-atrial pressure (RAP; p=0.010) and SvO₂ (p=0.003) were significant predictors, and pulmonary arterial compliance (PAC) showed a borderline association (p=0.066).

In multivariable models including REVEAL, Cox regression identified three independent predictors: higher RAP (HR 1.17; 95% CI 1.05–1.29; p=0.003), lower PAC (HR 19.43; 95% CI 1.86–202.63; p=0.013), and higher REVEAL score (HR 1.54; 95% CI 1.12–2.12; p=0.003).

In the model including COMPERA, independent predictors were RAP (HR 1.19; 95% CI 1.07–1.33; p=0.002), PAC (HR 15.79; 95% CI 1.44–172.64; p=0.024), and COMPERA score (HR 3.86; 95% CI 1.16–12.84; p=0.027). Clinically meaningful increments showed that each 1-mmHg increase in RAP conferred a 17–19% increase in hazard, and that PAC remained a very strong predictor in both models.

In the REVEAL intermediate-risk subgroup, SvO₂ and RAP provided significant prognostic discrimination (Log-Rank p=0.005 and p=0.027, respectively) (Figure 1).

Conclusions

RAP, SvO₂, and PAC significantly enhance risk discrimination beyond REVEAL and COMPERA, supporting the integration of invasive hemodynamics into routine multiparametric risk assessment.For image description, please refer to the figure legend and surrounding text.