Campbell C D, Tolitano D J, Weber K T, Statler P M, Replogle R L
Department of Surgery, Michael Reese Hospital and Medical Center, Chicago, Illinois 60616.
J Card Surg. 1988 Sep;3(3):181-91. doi: 10.1111/j.1540-8191.1988.tb00238.x.
Cardiac failure remains a life-threatening complication for certain patients undergoing intracardiac repair. Despite improvements in surgical techniques, methods of myocardial protection, and postoperative care, patients are frequently at risk to develop postoperative low output syndrome. Approximately 1% of cardiac surgical patients cannot be weaned from extracorporeal circulation in spite of adequate volume loading, the use of inotropic support, and initiation of intraaortic balloon pumping. In these cases, ventricular assist devices (VAD) can mechanically aid the failing heart and reverse the low output state. The concept of mechanical support for the failing left ventricle was first proposed by Clauss et al. in 1961. By 1968, Kantrowitz and associates had developed and refined the first intraaortic balloon pump (IABP). Through the efforts of Moulopolous and others, this device evolved into the present-day intraaortic balloon pump (IABP). Clinical evidence for the efficacy of left ventricular assist devices (LVAD) remained questionable until 1980, when the National Heart, Blood and Lung Institute evaluated short-term LVADs by comparing various types of mechanical aids. This report focused attention primarily on the failing left ventricle (LV). As the use of inotropic support, intraaortic balloon pumping, and LVADs improved, a small group of patients emerged who could not be separated from extracorporeal circulation due to a failing right ventricle. The failing right ventricle emerged as a unique clinical entity similar to postcardiotomy left ventricular failure that also benefited from mechanical cardiac assistance. Current therapy at major centers incorporating mechanical assist devices is based on the premise that the low output state will allow the failing heart to recover from a reversible injury. The frequent occurrence of postcardiotomy ischemia may be due to several factors such as poor myocardial protection, overdistension of the LV, emboli, coronary spasm or technical problems. Whatever the etiology, the end product of cardiac failure is a demand for oxygen consumption that cannot be met, thus leading to cardiac demise.
对于某些接受心内修复手术的患者而言，心力衰竭仍然是一种危及生命的并发症。尽管手术技术、心肌保护方法及术后护理都有所改进，但患者仍常常面临发生术后低心排血量综合征的风险。尽管进行了充分的容量负荷、使用了正性肌力药物支持并启动了主动脉内球囊反搏，但仍有大约1%的心脏手术患者无法脱离体外循环。在这些情况下，心室辅助装置（VAD）可机械辅助衰竭的心脏并逆转低心排血量状态。1961年，克劳斯等人首次提出了对衰竭左心室进行机械支持的概念。到1968年，坎特罗维茨及其同事研制并改进了第一台主动脉内球囊泵（IABP）。通过穆洛波洛斯等人的努力，该装置演变成了如今的主动脉内球囊泵（IABP）。直到1980年，美国国立心肺血液研究所通过比较各种机械辅助装置对短期左心室辅助装置（LVAD）进行评估时，左心室辅助装置（LVAD）疗效的临床证据仍存在疑问。该报告主要关注的是衰竭的左心室（LV）。随着正性肌力药物支持、主动脉内球囊反搏及左心室辅助装置（LVAD）应用的改进，出现了一小部分因右心室衰竭而无法脱离体外循环的患者。衰竭的右心室成为一种独特的临床实体，类似于心脏术后左心室衰竭，同样受益于机械性心脏辅助。主要中心目前采用机械辅助装置的治疗基于这样一个前提，即低心排血量状态将使衰竭的心脏从可逆性损伤中恢复。心脏术后缺血的频繁发生可能是由于多种因素，如心肌保护不佳、左心室过度扩张、栓子、冠状动脉痉挛或技术问题等。无论病因如何，心力衰竭的最终结果都是氧耗需求无法得到满足，从而导致心脏死亡。
