PERTs have been developed to offer standardised, patient specific therapy when presenting with an acute pulmonary embolism. progressively common allowing clinicians to offer tailored care to the patient with PAH. In 1991 a seminal paper by DAlonzo diagnosed 194 American patients with idiopathic pulmonary hypertension over a 4-12 months period, and suggested their mortality was closely linked to right ventricular function (1). By measuring three parameters: mean pulmonary artery pressure, mean right atrial (RA) pressure and cardiac index (CI) a National Institute for Health equation was derived to Exatecan mesylate help determine a PAH patients prognosis. The authors themselves however stressed that this equation result should be used alongside other clinical parameters. A later KEL study however, by Sandoval exhibited the utility of the NIH equation and discovered it to have a high sensitivity but poor specificity to predict survival (2). Decades later, further risk scores have been developed demonstrating our improved understanding and management of the disease. The French Pulmonary Hypertension Network enrolled 354 patients with idiopathic, familial and anorexigen-associated PAH in their registry. A prognostic score was developed which included the variables gender, exercise capacity and cardiac output at diagnosis (3). A few years later the Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL) registry prognostic equation was released and a subsequent risk score derived. REVEAL which is a multicenter US registry utilized 504 incident cases of idiopathic, familial and drug induced PAH to validate the equation and risk score which was developed from a cohort of 2,716 individuals. The REVEAL prognostic equation unlike the NIH equation included variables such as subclass of PAH, lung function and echocardiographic parameters (4). Unsurprisingly this equation was more accurate than the initial NIH prognostic equation. The REVEAL risk score calculator derived from the equation also included clinical observations, renal dysfunction, diffusing capacity of the lung for carbon monoxide (DLCO), as well as the standard markers of right ventricular function and functional capacity. The score produced ranged between 0C22. Low risk patients having a predicted 1 year survival of 95C100%, 90C95% in the average group, 85C90% in the moderately high-risk group, 70C85% in the high-risk group and 70% in the very high-risk group (5). In 2015 a joint collaboration between the US and French groups independently validated their risk equations and scores. The REVEAL risk score was applied retrospectively to the French cohort and the French risk equation to the REVEAL cohort. This exhibited that both prognostic scores offered good calibration and accuracy in a different geographic populace of PAH patients (6). After such formative work the 2015 ERS/ESC guidance strongly recommended the use of risk assessment when evaluating patients. Akin to the REVEAL risk score this ERS/ESC assessment compromises of clinical, biochemical, imaging, haemodynamic data, and exercise capacity. This risk score was based on the evidence of known good prognostic factors conveying an improved prognosis, specifically: WHO functional capacity ICII, a 6-minute walk distance (6MWD) 440 m, RA pressure Exatecan mesylate 8 mmHg, and a cardiac index (CI) 2.5 L/min/m2, mixed venous oxygen saturations (SvO2) 65% as well as brain natriuretic peptide (BNP) 50/N-terminal pro b-type natriuretic peptide (NT-pro BNP) 300 (7). With an aim to simplify risk assessment the 2017 study by Boucly ascertained in their cohort of 1 1,017 idiopathic, familial and drug induced PAH patients that four variables of WHO FC, 6MWD, RA pressure and CI allowed a clinician to ascertain transplant free survival at diagnosis and at the 12-month assessment of an individual. The team interestingly also revealed that the presence of low risk criteria at the 12-month assessment categorised patients at low long term risk, with improved diagnostic accuracy than a classification of low risk at presentation (8), these study findings were also found on a Exatecan mesylate smaller scale in an earlier study by Nickel (9). At the ERS Congress this year Professor Sitbon launched the results of a post hoc analysis from your GRIPHON study. It revealed the usefulness of prognostic and predictive value of risk assessment utilising the quantity of low risk variables in the largest ever cohort of PAH patients. Whilst it is widely accepted that the low risk category is usually associated with a superior prognosis, little data exists into what effect an improvement in functional end result measures.