Table. Criteria for “atypical” pulmonary arterial hypertension (based on the recommendations of the second Cologne Consensus Conference).

Hemodynamic ‧profile	Corresponds to that of other forms of PAH,i.e., precapillary PH with elevated PVR
Phenotypic ‧characteristics	Predominantly older patients (mostly >65 years);risk profile or comorbidities as in patients with left heart ‧disease or lung disease
Cardiac phenotype	At least three of the following risk factors:hypertension, coronary heart disease, diabetes mellitus, ‧obesity (BMI >30 kg/m2); further ‧characteristics including left atrial enlargement, atrial fibrillation
Pulmonary ‧phenotype	Normal or near-normal whole-body plethysmography, no clinically significant alterations of lung ‧parenchyma on chest CT, DLCO <45 % of reference value, often hypoxemia

BMI, Body mass index; CT, computed tomography; DLCO, diffusion capacity of lungs for carbon monoxide; PAH, pulmonary arterial hypertension; PH, pulmonary hypertension; PVR, pulmonary vascular resistance