The Right Ventricle and Pulmonary Circulation: Basic Concepts
The Right Ventricle and Pulmonary Circulation: Basic Concepts
复制标题
DOI：
10.1016/s0300-8932(10)70012-9
复制
发表时间：
2010-01-01
影响因子：
5.9
通讯作者：
Greyson, Clifford R.
中科院分区：
文献类型：
--
作者：
Greyson, Clifford R.
右心室和肺循环的主要目的是气体交换。由于气体交换发生在薄而高透性的肺泡膜中，因此肺压力必须保持低水平以避免肺水肿；因为右心室和肺与左心室和体循环是串联的，所以整个心输出量必须通过肺。与体循环对左心室的需求相比，这种低压、高容积的系统对右心室的需求截然不同。此外，右心室和肺循环必须缓冲由呼吸、体位变化和左心室心输出量变化引起的血容量和流量的动态变化。为满足这些相互冲突的需求而进行的优化导致补偿后负荷或压力增加的能力降低。不幸的是，大量的病理过程可导致急性和或慢性后负荷应激增加。当负荷后应激升高时，右心衰可能发生，血流动力学不稳定和死亡可能突然发生。已经确定了几种可能参与适应或不适应过度压力负荷的生化途径。
The primary purpose of the right ventricle and pulmonary circulation is gas exchange. Because gas exchange occurs in thin, highly permeable alveolar membranes, pulmonary pressure must remain low to avoid pulmonary edema; because the right ventricle and the lungs are in series with the left ventricle and the systemic circulation, the entire cardiac output must pass through the lungs. This low pressure, high volume system, makes dramatically different demands on the right ventricle compared with the demands made on the left ventricle by the systemic circulation. Moreover, the right ventricle and pulmonary circulation must buffer dynamic changes in blood volume and flow resulting from respiration, positional changes, and changes in left ventricular cardiac output.The optimizations needed to meet these conflicting demands result in reduced capacity to compensate for increased afterload or pressure. Unfortunately, a large number of pathologic processes can result in acute and or chronic increases in afterload stress. As afterload stress rises, right heart failure may develop, and hemodynamic instability and death can occur abruptly. Several biochemical pathways have been identified that may participate in adaptation or maladaptation to excessive pressure loads.