動静脈間シャントが循環動態におよぼす影響 ：動物実験ならびに臨床症例による検討

Abstract

The experimental and clinical studies were carried out to clarify the effects of arteriovenous shunt (AVS) on cardiac hemodynamics and organic circulation. In the experimental study using 7 mongrel dogs, AVS was made between the femoral artery and vein, and its blood flow was regulated equivalent to 20% of cardiac output. Changes in cardiac hemodynamics and in organic circulation especially in renal one, due to opening and closing AVS were observed. In the clinical study for 10 patients with end-stage renal disease, their cardiac hemodynamics were evaluated before and after the AVS formation by echocardiography and mechanocardiography. For the experimental study, opening AVS induced a slight decrease in total peripheral vascular resistance, significant increase in cardiac output, transient descent in aortic blood pressure, and ascent in inferior caval pressure. And a transient fall in renal blood pressure was observed, neither renal blood flow nor renal vascular resistance were changed. Recovery of cardiac hemodynamic indices due to closing AVS were delayed as compared with renal circulatory ones. For the clinical study, the increase in stroke volume, minute cardiac output and mean circumferential fiber shortening velocity of the left ventricle were observed after AVS formation. It seems that the AVS caused a hyperkinetic circulatory state with increase in venous return and consequent increase in cardiac contractility. Therefore, it must be careful that the hyperkinetic state mentioned above may bring a high output heart failure.