The iPAH Registry was set up and run by the Association in parallel to the CTEPH Registry. Its main objective was to identify the risk factors and clinical conditions associated to CTEPH vs. other pulmonary vascular diseases.

Of particular interest is the differentiation between idiopathic pulmonary arterial hypertension (iPAH) and CTEPH, as the clinical und underlying pathophysiological distinction between iPAH and CTEPH is challenging upon a patient’s first presentation in the clinic. Results are expected to provide supportive data for the differential diagnosis of CTEPH vs. iPAH and thus to help differentiate in a clinical setting between iPAH and CTEPH.

158 iPAH patients with normal scintigrams at diagnosis were identified from and included by 8 of the large centres which had also been participating in the CTEPH Registry. Patients diagnosed on or after September 1, 2006 were included. Inclusion period lasted from May 2010 until April 2011.

Data have been analysed and a first manuscript has been published (Lang et al. Factors associated with diagnosis and operability of chronic thromboembolic pulmonary hypertension. A case-control study. Thromb Haemost 2013; 110:83-91. pdf)