NPPB and pulmonary arterial hypertension: The REVEAL Risk Score encompasses PAH risk factors including demographic data, comorbidities, NYHA/WHO group I subgroup, NYHA/WHO functional class, vital signs, 6-minute walk distance, and brain natriuretic peptide along with echocardiographic, pulmonary function testing, and hemodynamic risk factors, in a risk score prognostic model.32 Although it is evident that the REVEAL Risk Score captures most, if not all, known prognostic risk factors in PAH, the possibility of an unknown possible factor cannot be excluded.