高频超声心动图观察低血钾对免心脏结构及功能的影响

目的 应用经胸高频超声实时监测低血钾时不同钾离子浓度对实验兔心脏结构及心脏功能的影响,探讨血钾离子浓度与心脏功能改变的相关性,为临床早期诊断及治疗提供依据.方法 通过给实验兔肌注速尿溶液建立低钾动物模型,采用M型超声心动图实时监测心脏形态、内部血流频谱动态变化及其功能变化,并对心脏组织进行病理学观察.结果 血钾浓度降低初期和中期,实验兔心脏形态和功能变化不大,当血钾降低到2.0±0.3 mmol/L,心腔迅速扩大,心脏功能降低,直至心脏停博.心肌病理切片显示心肌细胞肿胀,胞质内大量空泡形成.结论 低血钾可以使实验兔的心脏结构及功能发生一系列变化,超声心动图可以无创、准确、实时地监测这种改变,并随时评价心脏功能,因此,超声心电图对监测因低钾引起的心脏并发症提供了一种便捷可靠的方法.

The Changes of Cardiac Structure and Function Induced by Hypokalemia with Echocardiography

Objective To explore the correlation between serum potassium levels and the changes of the heart, the real-time echocardiography was applied to monitor the effects of hypokalemia on the heart structure and function of the experimental rabbits, and for the purpose of early diagnosis and treatment in the clinical practice. Methods The hypokalemia experimental model was established by intramuscular furosemide injection. M-mode echocardiography was used to monitor the cardiac morphology, the sequential variation of flow spectrum and cardiac function. After that, the heart was removed and the tissue was made into pathological section and dyed with HE. Results The cardiac morphology and function of the rabbits showed little change during the early and middle stage. Then, the heart dilated rapidly, and its function decreased until cardiac arrest. The myocardial pathological section showed swell and vacuolization of the myocardial cells. Conclusion There were a series of changes in the heart of rabbit during the decreasing process of serum potassium concentration, and echocardiography is a noninvasive method to monitor these changes, it can observe the heart morphology and evaluate the cardiac function accurately in real time. Thus, echocardiography provides a convenient and reliable method for monitoring the heart complications induced by hypokalemia.