The Left Heart System
摘要
The left heart system consists of the venous sub-system, the left ventricle and systemic arterial system. Abnormalities of left ventricular and/or systemic vascular function are major causes of circulatory failure. This chapter will firstly discuss left ventricular function and ventriculo-arterial coupling based on the elastance model, from which the determinants of left ventricular ejection fraction will be evident. Secondly, the physiology of systemic arterial blood pressure and its derivative, systemic vascular resistance will be discussed, based on recent insights from the reservoir wave model. Thirdly, the autoregulation of blood pressure and regional or organ-specific blood flow will be discussed, including the effects of vasoconstriction.