[Etiopathogenesis of venous thrombosis and pulmonary thromboembolism: pathophysiologic changes in the cardiovascular system].

It is known that pulmonary embolism is accompanied by quite complex pathophysiological changes in cardiovascular system. From cardiovascular point of view, the diagnosis of pulmonary thromboembolism may be easily based on echocardiographic signs of right ventricular hypokinesia. Physiologic abnormalities caused by venous emboli are related to the cross-sectional area of occluded pulmonary arterial bed. Recent studies has demonstrated, that in patients with massive pulmonary thromboembolism and signs of pulmonary hypertension, increase of right ventricular afterload can lead to both right ventricular failure and reduction of left ventricular preload. Despite development of pulmonary hypertension in acute massive pulmonary thromboembolism, there are no signs of right ventricular hypertrophy. The main ECG changes include right ventricular overload. Previous normal ECG is of special importance. Documentation of serious increase of pulmonary arterial pressure by Doppler echocardiography will assist to link right ventricular pressure overload and dysfunction with embolisms. Transesophageal echocardiography had the similar diagnostic value as transthoracic one, but especially is helpful in bedside diagnosis in patients with signs of shock secondary to pulmonary thromboembolism.