<unk> <unk>  is a long-term disease caused by a blockage in the blood vessels that deliver blood from the heart to the lungs (the pulmonary arterial tree). These blockages cause increased resistance to flow in the pulmonary arterial tree which in turn leads to rise in pressure in these arteries (pulmonary hypertension). The blockages either result from organised (or hardened) blood clots that usually originate from the deep veins of the lower limbs of the body <unk> m) and lodge in the pulmonary arterial tree after passing through the right side of the heart. The blockages may also result from scar tissue that forms at the site where the clot has damaged the endothelial lining of the pulmonary arteries, causing permanent fibrous obstruction (blood flow blockage). Most patients have a combination of microvascular (small vessel) and macrovascular (large vessel) obstruction. Some patients may present with normal or near-normal pulmonary pressures at rest despite symptomatic disease. These patients are labelled as having<unk><unk>  disease (CTED). Diagnosis is based on findings obtained after at least 3 months of effective anticoagulation therapy (blood thinners) in order to discriminate this condition from ‘subacute’ pulmonary embolism (blood clot in the lungs, PE). Diagnostic findings for<unk>  are: # Invasively (i.e., in the blood) measured mean pulmonary arterial pressure (mPAP) ≥25 mmHg; # Mismatched perfusion defects on lung ventilation/perfusion (V/Q) scan and specific diagnostic signs for<unk>  seen by multidetector computed tomography angiography (MDCT), magnetic resonance imaging (MRI) or conventional pulmonary cineangiography (PAG), such as ring-like stenoses, webs/slits,<unk>  total occlusions (pouch lesions, or tapered lesions) and tortuous lesions.
Chronic thromboembolic pulmonary hypertension
Pulmonary hypertension
Portopulmonary hypertension
Pulmonary venoocclusive disease
Absent pulmonary valve syndrome
Bilharzial cor pulmonale
Asthma
Lettuce big-vein disease