Oral or intravenous beta-blockers in acute myocardial infarction
Date First Published:
March 1, 2000
Last Updated:
July 6, 2001
Report by:
Steve Jones, Clinical Research Fellow (Manchester Royal Infirmary)
Search checked by:
Ian Crawford, Manchester Royal Infirmary
Three-Part Question:
In [an acute myocaridal infarction] is [IV beta-blockade better than oral beta-blockade] at [reducing mortality and decreasing morbidity]?
Clinical Scenario:
A 45 year old man is brought to the emergency department with acute, central chest pain. You have diagnosed an acute myocardial infarction from the ECG for which he is receiving thrombolysis. You know that giving him a beta-blocker will improve his outcome but you only have tablets in the department and wonder whether he will be at a disadvantage for receiving this rather than an intravenous dose.
Search Strategy:
Medline 1966-12/00 using the OVID interface.
Search Details:
[{exp myocardial infarction OR myocardial infarction.mp} AND {exp adrenergic beta-antagonists OR beta blockers.mp} AND {exp administration, oral OR exp oral medicine OR oral.mp}] AND maximally sensitive RCT filter LIMIT to human AND english.
Outcome:
143 papers found of which 142 were irrelevant or of insufficient quality. The remaining paper is shown in the table.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Atenolol use and clinical outcomes after thrombolysis for acute myocardial infarction: the GUSTO-I experience. Global Utilization of Streptokinase and TPA (alteplase) for Occluded Coronary Arteries. Pfisterer M, Cox JL, Granger CB et al. 1998, Switzerland | Patients with acute MI No atenolol (n=10,073) vs any atenolol (n=30,771) Any intravenous atenolol (n=18,200) vs oral atenolol only (n=12,545) vs both intravenous and oral drug (n=16,406) |
Prospectively planned observational analysis of the GUSTO-I dataset (a multicentre PRCT) | Mortality any atenolol vs none | 30-day mortality was significantly lower in atenolol-treated patients. | Observational study rather than PRCT Poor power due to subanalysis Early deaths treated as "no atenolol" before adjustments |
| Mortality IV atenolol vs oral | More likely to die (odds ratio 1.3 [95% CI 1 - 1.5] p=0.02) with IV | ||||
| Morbidity | More heart failure, shock, recurrent ischaemia and pacemaker use. |
Author Commentary:
Although atenolol appears to improve outcomes after thrombolysis for myocardial infarction, early intravenous atenolol seems of limited value. The best approach for most patients may be to begin oral atenolol once stable. More work will need to be done.
Bottom Line:
Oral beta-blockers are better than IV beta-blockers in stable AMI patients.
References:
- Pfisterer M, Cox JL, Granger CB et al.. Atenolol use and clinical outcomes after thrombolysis for acute myocardial infarction: the GUSTO-I experience. Global Utilization of Streptokinase and TPA (alteplase) for Occluded Coronary Arteries.