Critical Care Medicine-Neurologic Disorders>>>>>Heart Failure
Question 4#

A 72-year-old male with coronary artery disease presents 5 days after experiencing chest pain complaining of dyspnea. He is in the emergency department with heart rate 87 beats/min and blood pressure 86/42 mm Hg, oxygen saturation 91% on 50% oxygen via facemask. You do a bedside echocardiogram and find that he has a depressed ejection fraction and severe mitral regurgitation. A formal echocardiogram was performed and a ruptured papillary muscle identified. His other lab values are significant for lactate 5.6 mmol/L and creatinine 2.01 mg/dL. You place him on BIPAP to improve oxygenation and inotropes to augment perfusion. Despite these measures, he continues to have worsening metabolic acidosis and now LFTs are rising. An intra-aortic balloon pump (IABP) is placed and the patient is being prepared to go to the operating room.

Which of the following is NOT true regarding IABP?

a. IABP is the most commonly used mechanical support device
b. It has been shown to improve mortality in patients with cardiogenic shock
c. It has been indicated for patients with mechanical complications from myocardial infarction such as a ventricular septal defect and mitral regurgitation
d. It is contraindicated in a patient with aortic insufficiency
e. Helium is used to inflate the balloon

Correct Answer is B

Comment:

Correct Answer: B

The IABP is the most commonly used mechanical circulatory support device. Indications for IABP include cardiogenic shock, postmyocardial infarction, cardiomyopathy, and complications of acute myocardial infarction such as acute ventricular septal defect and mitral regurgitation. The IABP-SHOCK II trial randomized 600 patients with cardiogenic shock from myocardial infarction to receive IABP or not. It showed no difference in mortality, length of stay in the intensive care unit, renal function, sepsis, stroke, or peripheral ischemic complications. Some contraindications for IABP insertion include aortic dissection, severe aortic insufficiency, severe coagulopathy, and tachyarrhythmias. Helium is used to inflate the balloon because of its low viscosity and quick elimination if the balloon ruptures.

References:

  1. Gold HK, Leinbach RC, Sanders CA, et al. Intraaortic balloon pumping for ventricular septal defect or mitral regurgitation complicating acute myocardial infarction. Circulation. 1973;47:1191.
  2. Ibanez B, James S, Agewall S, et al. 2017 ESC guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: the task force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC). Eur Heart J. 2018;39:119.