Pulmonary arterial hypertension (PAH) is a chronic disease of the pulmonary vasculature characterized by progressive narrowing of the pulmonary arteries, which in turn leads to increased pulmonary vascular resistance, right heart failure, and death.¹ There has been a significant improvement in the available medical therapeutic options in this field that have impacted the short-term survival and morbidity in these patients.² However, the median survival post-diagnosis stays limited at 7 years.³ Physicians' ability to predict PAH disease progression allows them to determine the patient's prognosis, identify treatment goals, and monitor his or her response to therapy.⁴ If widely adopted, risk prediction can enhance the consistency of treatment approaches and improve the timeliness of referral for lung transplantation. This allows for an optimal, directed care that ultimately reduces morbidity and improves mortality in patients with PAH.

IMPORTANT FACTORS FOR RISK STRATIFICATION

Like our patients with PAH, risk stratification should have a multifaceted approach that includes both objective and subjective variables that ultimately create an overall risk profile. These parameters should be statistically validated and evidence based. The following factors have been cited in literature in their implications for patient outcomes:

TOOLS FOR RISK STRATIFICATION

There are various risk calculators that are available to risk stratify patients with PAH that all focus on different aspects of the disease process. The primary aim of these assessments is to project patient trajectory based on available information, allowing for informed and individualized decision-making. Ideally, these tools should be multifaceted, applicable along the continuum of disease, easy to use, and validated. Analysis of the Registry to Evaluate Early and Long-term PAH Disease Management data produced a versatile risk calculator based on over 2,500 PAH registry patients who were newly and previously diagnosed with PAH (Table 1).^6,10 Similarly, the European PAH registries (French Pulmonary Arterial Hypertension Network registry, Spanish Registry Of Pulmonary Arterial Hypertension, Swedish Pulmonary Arterial Hypertension Registry, and Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension) have developed algorithms to stratify patients as low, intermediate, or high risk of death and are represented in the 2015 European Society of Cardiology and European Respiratory Society pulmonary hypertension guidelines (Table 2).^8,11,12 These registries and evaluations of clinical trial sets have provided important insights into the importance of both modifiable (e.g., 6-minute walk distance, functional class, and BNP) and nonmodifiable (e.g., age, gender, and PAH etiology) risk factors that predict survival.

TAKE-HOME POINTS

When managing patients with PAH, risk assessment should play a vital role in the care delivered to the patient. To accurately prognosticate and provide evidence-based treatment plans to the patient should be of utmost importance. The various risk calculators, such as that from the Registry to Evaluate Early and Long-term PAH Disease Management, have been validated and are effective at providing the patient and physician with valuable information to predict mortality and prognosis and ultimately provide appropriate treatment.

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