Pulmonary arterial hypertension or left heart disease with pulmonary hypertension? Toward noninvasive clarity, but time for a new paradigm

Abstract

@ERSpublications PAH or left heart disease with PH? Perspective on group 1 and 2 PH differentiators and a call for a unified approach http://ow.ly/OtRxU Widespread availability of Doppler echocardiography, combined with increasing community awareness of pulmonary arterial hypertension (PAH) as an important and treatable disease, results in frequent referral of patients with suspected PAH to tertiary pulmonary hypertension centres. While this state of affairs is laudable, it does result in substantial numbers of patients who turn out not to have PAH being seen at tertiary pulmonary hypertension centres. In this issue of the European Respiratory Journal, JACOBS et al. [1] describe the retrospective development and prospective validation of a simple tool designed to improve accurate noninvasive distinction between PAH and pulmonary hypertension due to left heart disease (systolic, diastolic or valvular; World Classification of pulmonary hypertension group 2). This tool was derived from analysis of patients with PAH or group 2 pulmonary hypertension seen at a major European pulmonary hypertension centre. It may enhance noninvasive exclusion of group 1 PAH in a subset of patients seen with pulmonary hypertension who have risk factors for group 2 pulmonary hypertension.The tool utilises a combination of historical, echocardiographic and electrocardiographic parameters to create a risk score for presence of pulmonary hypertension related to left heart disease, defined as a pulmonary capillary wedge pressure or left ventricular end diastolic pressure >15 mmHg, or rising above that level following administration of 500 cm 3 i.v. saline. A risk score of ⩾64 had a positive predictive value of 92% for presence of pulmonary hypertension related to left heart disease with a specificity of 99%, i.e. misclassifying one in 100 PAH patients. A score of 64 can be achieved simply by having a clinical history of left heart disease combined with echocardiographic findings of left atrial enlargement and more than mild left valve disease.A remarkably higher proportion of patients were confirmed to have PAH (79% in the development cohort and 59% in the validation cohort) than would be the case in a community cohort, where group 2 pulmonary hypertension would be of much greater prevalence. Accordingly, the authors appropriately describe the need for validation of this tool in a community cohort prior to utilisation in clinical practice.The authors settle on a risk score of 72 as a cut-off value beyond which there is no need to suspect PAH and to refer to a pulmonary hypertension centre, since one in 100 patients ultimately felt to have PAH had risk scores above 64, and 100% specificity was felt important in order not to miss any PAH cases. This

S100A12 as a marker of worse cardiac output and mortality in pulmonary hypertension

“…6 The National Heart, Lung, and Blood Institute Pulmonary Vascular Disease Phenomics (PVDomics; RFA-HL-14-027) 7 and other groups 8 are evaluating better ways to phenotype PH patients. The use of molecular biomarkers is one way to better phenotype these patients.…”

“…[2][3][4][5] Predicting prognosis in PH has been limited, as classifying and phenotyping patients with PH are largely 'based on a relatively simple combination of patient characteristics and hemodynamics'. 6 The National Heart, Lung, and Blood Institute Pulmonary Vascular Disease Phenomics (PVDomics; RFA-HL-14-027) 7 and SUMMARY AT A GLANCE S100A12 serum levels are elevated in patients with pulmonary hypertension and they are associated with increased mortality rates. These findings show that the S100A12 biomarker has a major role to play in determining the prognosis of pulmonary hypertension patients, and they would enrich deep phenotyping efforts in this patient population.…”

Structural and Hemodynamic Changes of the Right Ventricle in PH-HFpEF

“…Compared to the PAH phenotype, PH-HFpEF is characterized by specific demographic, clinical, and echocardiographic features, including older age, female gender, hypertension, higher rate of atrial fibrillation, and metabolic syndrome (hyperlipidaemia, obesity, diabetes, and hypertension) [18] (Table 1). Many scores have been proposed so far [18][19][20][21][22][23][24], integrating features analysed from retrospective single centre studies; some have even suggested that simple clinical characteristics alone, without echocardiographic or hemodynamic data, were able to differentiate PH-HFpEF from PAH [25]. No score has been externally validated so far, but a similar approach has recently been proposed to assess HFpEF among patients with chronic heart failure.…”