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

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.