A new small randomized trial suggests that early intravenous metoprolol, early after symptoms and prior to PCI for anterior STEMI, reduces infarct size.
History
–The data for beta blockers in the pre-reperfusion era was positive.
—Based on this weak data, beta blockers were class I for STEMI for many years.
–However, the data for them in the thrombolytic era was not positive, and one might say is was negative (COMMIT trial from China, huge, showed no benefit and an increased rate of cardiogenic shock).
—Based on this, recommendations became class IIa: acute metolprolol only for patients with hypertension or ongoing ischemia. [The recommendation for use of beta blockers after the acute phase (24 hours) remained, and is a CMS core measure.]
–There has not been any good data on beta blockers in the PCI era.
Today, after this article
–This is only a small study that does not use hard outcomes like mortality, but it suggests that perhaps metoprolol is indeed useful in anterior STEMI prior to PCI. It would be premature to let it change management.
It is now an urgent question to answer: is early beta-1 blockade beneficial early in STEMI? Larger randomized trials with hard endpoints are necessary to answer it satisfactorily.
Abstract:
http://circ.ahajournals.org/content/128/14/1495.abstract
Editorial:
