Q: Which one of the following should be avoided in patients who are at high risk of cardiogenic shock (pre-shock state) secondary to acute myocardial infarction?

A) aspirin
B) beta-blocker
C) heparin
D) intra-aortic balloon pump 
E) GP IIb/IIIa inhibitors



Answer:  B

Though beta-blockers are mainstay of treatment in coronary artery disease they can be detrimental in acute phase after acute MI, in patients who are in pre-shock state (impending cardiogenic shock). This may be due to the fact that beta-blockers have negative inotropic effect. According to COMMIT trial randomization to early beta blockade in patients who have not developed shock yet, there was a 30 percent higher occurrence of cardiogenic shock in patients 

• Above age 70
•  systolic blood pressure (BP) less than 120 mm Hg 
•  heart rate greater than 110 beats per minute
•  those with Killip Class over 1

All other choices are in fact indicated in acute MI management.



Reference: 

Chen ZM, et al. "Early intravenous then oral metoprolol in 45 852 patients with acute myocardial infarction: randomised placebo-controlled trial". The Lancet. 2005. 366(9497):1622-1632.