A 72-year-old woman with type 2 diabetes mellitus is brought to the emergency department with dyspnea and chest pressure that started about 6 hours earlier.
Her blood pressure is 82/62 mm Hg and pulse is 104/min. Pulse oximetry shows 92% on 15 L oxygen by face mask. She is mildly confused. Examination shows moist oral mucosa and distended neck veins in a sitting position. The apical impulse is displaced to the left with a third heart sound. Lung examination shows fine crackles one third of the way up in bilateral lung fields. Lower extremities are cold to the touch with weak peripheral pulses.
Her initial ECG shows sinus tachycardia and a new left bundle branch block.
Which of the following measures instituted immediately is most likely to improve survival in this patient?

Question

A 72-year-old woman with type 2 diabetes mellitus is brought to the emergency department with dyspnea and chest pressure that started about 6 hours earlier.
Her blood pressure is 82/62 mm Hg and pulse is 104/min.  Pulse oximetry shows 92% on 15 L oxygen by face mask.  She is mildly confused.  Examination shows moist oral mucosa and distended neck veins in a sitting position.  The apical impulse is displaced to the left with a third heart sound.  Lung examination shows fine crackles one third of the way up in bilateral lung fields.  Lower extremities are cold to the touch with weak peripheral pulses.
Her initial ECG shows sinus tachycardia and a new left bundle branch block.
Which of the following measures instituted immediately is most likely to improve survival in this patient?

Quizplus · Accepted Answer

This patient's presentation with new left bundle branch block on ECG suggests acute myocardial infarction (MI) with cardiogenic shock. Cardiogenic shock is the leading cause of death in patients with acute ST elevation MI, with short-term hospital mortality rates approaching 50%. An important treatment goal in patients with cardiogenic shock resulting from acute MI is to restore coronary perfusion with primary percutaneous coronary intervention or emergency coronary artery bypass grafting. The benefit of early revascularization was shown in the SHOCK trial, which compared early revascularization to a strategy of initial medical stabilization. Early revascularization of the infarct-related artery limits infarct size and is associated with improved overall mortality. (Choice A) Hemodynamic monitoring is useful in patients with refractory shock after successful revascularization. However, reperfusion therapy should not be delayed for pulmonary artery catheter placement. (Choice B) Intra-aortic balloon pump is frequently used for rapid stabilization of patients with cardiogenic shock resulting from acute MI. It reduces afterload, increases mean arterial pressure, and improves coronary blood flow. However, studies have not shown any significant reduction in inpatient mortality with intra-aortic balloon pump. (Choice C) Intravenous inotropic agents such as milrinone and dobutamine can cause hypotension and may increase mortality rates in cardiogenic shock associated with acute MI. Norepinephrine would be a better treatment option for hypotension. (Choice D) Intravenous fluids and/or vasopressors can treat hypotension after volume status is assessed. Vasopressors (eg, norepinephrine) tend to maintain adequate blood pressure and improve tissue perfusion, but there is no conclusive evidence showing mortality rate reduction. Educational objective: Cardiogenic shock is the primary cause of death in patients hospitalized with acute myocardial infarction. Emergency revascularization with primary percutaneous coronary intervention or emergency coronary artery bypass grafting is the only therapy that has been shown to improve mortality in these patients. __________ References: Cardiogenic shock complicating myocardial infarction. (http://www.ncbi.nlm.nih.gov/pubmed/17964362)

A 72-Year-Old Woman with Type 2 Diabetes Mellitus Is Brought