PLASMA LP(A) LEVELS ARE INCREASED IN PATIENTS WITH CHRONIC THROMBOEMBOLIC PULMONARY-HYPERTENSION

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease res ulting from the thromboembolic obstruction of the segmental and/or lar ge size pulmonary arteries, subsequently leading to pulmonary arterial hypertension. Incomplete resolution of acute pulmonary emboli and thr ombus organization are believed to be important for the development of the disease. Primary pulmonary hypertension (PPH) is a further diseas e that at present is poorly understood but shows a clinical picture si milar to CTEPH. Since lipoprotein(a) [Lp(a)], a genetically determined risk factor for atherosclerosis and thrombosis, has been found increa sed in plasma of patients with deep vein thrombosis and pulmonary embo lism, we measured plasma Lp(a) levels in 40 patients with CTEPH and 50 patients with PPH and compared them to 50 matched controls. The media n for Lp(a) plasma levels was significantly higher in CTEPH patients ( 26.6 mg/dl) than in PPH patients (9.6 mg/dl) and controls (7.2 mg/dl). Increased plasma Lp(a) could, therefore, play a significant role in t he mechanisms of ongoing thrombosis and thrombus organization in CTEPH , while its possible role in PPH can be limited to a small number of p atients.