肺动脉高压的病因及分类:可根据肺动脉高压的临床、病理生理和病理改变进行分类,现分述于下。一、按临床病因分类:可分为原发和继发。(一)原发性肺动脉高压:为发病原因不明的肺动脉高压,可能由于原发性肺小动脉痉挛,和进行性肺小动脉的中层肥厚、内膜增生、胶原性血管病变、复发性微小动脉血栓引起。可根据临床病情、体征、胸片、心电图、心脏彩色多普勒超声、核素通气/灌注扫描等检查除外继发性肺动脉高压而诊断。依据这些检查,常仍难将原发性肺动脉高压和慢性反复性肺血栓栓塞、肺静 Pulmonary hypertension causes and classification: According to pulmonary hypertension clinical, pathophysiological and pathological changes are classified, are described below. First, according to the clinical etiology classification: can be divided into primary and secondary. (A) of the primary pulmonary hypertension: the pathogenesis of pulmonary hypertension, may be due to primary pulmonary arterial spasm, and progressive pulmonary arterial middle hypertrophy, intimal hyperplasia, collagen vascular disease, recurrent small artery Thrombosis caused. According to clinical conditions, signs, chest radiograph, ECG, cardiac color Doppler ultrasound, radionuclide / perfusion scan and other tests except for the diagnosis of secondary pulmonary hypertension. Based on these tests, it is often difficult to the primary pulmonary hypertension and chronic recurrent pulmonary thromboembolism, pulmonary static