每日一题_2022.5.10

A 43-year-old man is admitted to the ICU with nausea, vomiting, and jaundice. He says that the symptoms have been progressing over the past two months. His medical history is significant for end-stage non-ischemic cardiomyopathy, and he has a HeartMate II left ventricular assist device (LVAD). Current vital signs are: blood pressure 121/83 mm Hg, heart rate 98 beats/min, respiratory rate 14 breaths/min. His hemoglobin is 8.3 g/dL; four months ago it was 12.1 g/dL. His current lactate dehydrogenase is 2,123 U/L. His LVAD setting is 9,000 RPM, pulsatility index 1.3, and pump power 8.4 watts with occasional increases to 13 watts. Transthoracic echocardiography shows a well-filled left ventricular cavity and a ventricular septum with a slight rightward bow. His INR is 2.8.

Which of the following is the best treatment for this patient?

A. Continue observation.

B. Increase the RPM speed.

C. Increase anticoagulation therapy with a goal of raising INR to 4. 

D. Initiate pump exchange.

答案解析：

该患者乳酸脱氢酶升高，搏动指数低，泵浦功率高，提示泵浦血栓形成。随着他的器械中的血栓形成，LVAD的阻力增加，降低了其卸载心脏的能力。左心室现在必须通过主动脉瓣而不是通过器械排出大部分血液，这解释了正常的血压。溶栓治疗已被尝试用于清除LVAD中的血凝块负荷，取得了名义上的成功，但与较高的出血并发症风险相关。在泵血栓形成的情况下，增加LVAD速度将更多地出血。患者的INR适当；增加目标治疗将增加出血风险。最佳措施是更换器械。

正确答案：D