The evolution of the European risk stratification system for pulmonary arterial hypertension

Extract Pulmonary arterial hypertension (PAH) has remained a challenging disease with poor survival [1]. Accurate risk stratification in PAH is crucial for making treatment decisions and prognostication. Current European guidelines recommend routine risk assessment at baseline and follow-up evaluation [2]. Due to the complex nature of the disease and many factors influencing survival in PAH, it is recommended to have a multiparametric risk assessment in PAH [2–5]. Over the years, individual risk stratification tools have undergone refinements. For example, the Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) primary risk calculator evolved over the years from REVEAL 1.0 to REVEAL 2.0 and REVEAL lite 2 in order to incorporate new variables and realign older variables for improved versatility and applicability [3, 4, 6]. Thus, the purpose of evolving risk assessment tools is to improve their accuracy in predicting mortality and morbidity while keeping their ease of use in routine clinical practice. Since treatment strategy is intimately intertwined with the risk status of a patient, it is imperative to perform routine risk assessment with as much accuracy and precision as possible to prevent over- or underestimation of risk, so patients are assigned the most efficacious upfront therapy.