Department of Clinical Physiology and Nuclear Medicine, Hvidovre Hospital, Faculty of Health Sciences, University of Copenhagen, Denmark.
J Hepatol. 2010 Jul;53(1):179-90. doi: 10.1016/j.jhep.2010.02.023. Epub 2010 Mar 31.
Increased cardiac output was first described in patients with cirrhosis more than fifty years ago. Later, various observations have indicated the presence of a latent cardiac dysfunction, which includes a combination of reduced cardiac contractility with systolic and diastolic dysfunction and electrophysiological abnormalities. This syndrome is termed cirrhotic cardiomyopathy. Results of experimental studies indicate the involvement of several mechanisms in the pathophysiology, such as reduced beta-adrenergic receptor signal transduction, altered transmembrane currents and electromechanical coupling, nitric oxide overproduction, and cannabinoid receptor activation. Systolic incompetence in patients can be revealed by pharmacological or physical strain and during stressful procedures, such as transjugular intrahepatic portosystemic shunt insertion and liver transplantation. Systolic dysfunction has recently been implicated in development of renal failure in advanced disease. Diastolic dysfunction reflects delayed left ventricular filling and is partly attributed to ventricular hypertrophy, subendocardial oedema, and altered collagen structure. The QT interval is prolonged in about half of the cirrhotic patients and it may be normalised by beta-blockers. No specific therapy for cirrhotic cardiomyopathy can be recommended, but treatment should be supportive and directed against the cardiac dysfunction. Future research should better describe the prevalence, impact on morbidity and survival, and look for potential treatments.
早在五十多年前,人们就首次在肝硬化患者中观察到心输出量增加。后来,各种观察结果表明存在潜在的心脏功能障碍,包括收缩和舒张功能障碍以及电生理异常的心肌收缩力降低的组合。这种综合征被称为肝硬化性心肌病。实验研究结果表明,几种机制参与了其病理生理学过程,如β-肾上腺素能受体信号转导减少、跨膜电流和机电耦联改变、一氧化氮生成过多以及大麻素受体激活。通过药理学或物理负荷以及在有压力的过程中(如经颈静脉肝内门体分流术插入和肝移植)可以揭示患者的收缩功能不全。收缩功能障碍最近与晚期疾病中的肾衰竭发展有关。舒张功能障碍反映左心室充盈延迟,部分归因于心室肥厚、心内膜下水肿和胶原结构改变。大约一半的肝硬化患者的 QT 间期延长,β受体阻滞剂可使其正常化。目前尚不能推荐针对肝硬化性心肌病的特定治疗方法,但治疗应是支持性的,并针对心脏功能障碍进行。未来的研究应更好地描述其患病率、对发病率和生存率的影响,并寻找潜在的治疗方法。