Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-23T07:31:02.807Z Has data issue: false hasContentIssue false
  • English
  • Français

Do β-blockers reduce short-term mortality following acute myocardial infarction? A systematic review and meta-analysis

Published online by Cambridge University Press:  21 May 2015

Abdullah Al-Reesi ,
Nabil Al-Zadjali ,
Jeff Perry ,
Dean Fergusson ,
Mohammed Al-Shamsi ,
Majid Al-Thagafi  and
Ian Stiell
Abdullah Al-Reesi*
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont.
Nabil Al-Zadjali
Affiliation:
Department of Epidemiology and Community Medicine, University of Ottawa, Ottawa, Ont.
Jeff Perry
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont.
Dean Fergusson
Affiliation:
Department of Emergency Medicine, Sultan Qaboos University Hospital, Muscat, Oman
Mohammed Al-Shamsi
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont.
Majid Al-Thagafi
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont.
Ian Stiell
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont.
*
Department of Emergency Medicine, Clinical Epidemiology Unit, F6, Ottawa Health Research Institute, 1053 Carling Ave., Ottawa ON K1Y 4E9; [email protected]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
Objective:

Acute myocardial infarction (AMI) remains a major cause of death and β-blockers are known to reduce long-term mortality in post-AMI patients. We sought to determine whether patients receiving β-blockers acutely (within 72 h) following AMI had a lower mortality rate at 6 weeks than patients receiving placebo.

Methods:

We conducted a systematic review of randomized controlled clinical trials that assessed 6-week mortality and compared β-blockers with placebo in patients randomized within the first 72 hours following AMI. We searched these databases: MEDLINE (1966–2006), EMBASE (1980–2007), Cochrane Central Register of Controlled Trials, Health Star (1966–2007), Cochrane Database for Systematic Reviews, ACP Journal Club (1991–2007), Database of Abstracts of Reviews of Effect (< 1st quarter 2007) and Conference Papers Index (1984–2007). Two blinded reviewers extracted the data and rated study quality using the Jadad score and the adequacy of allocation concealment score, which was adopted by the Cochrane group. We calculated pooled odds ratios (ORs) using a random effect model and performed sensitivity analyses to explore the stability of the overall treatment effect.

Results:

We included 18 studies (13 were rated high-quality) with 74 643 enrolled participants and had 5095 deaths. Compared with placebo, adding β-blockers to other interventions within 72 hours after AMI did not result in a statistically significant reduction in 6-week mortality (OR 0.95, 95% confidence interval [CI] 0.90–1.01). When restricted to high quality studies, the OR for 6-week mortality reduction was 0.96 (95% CI 0.91–1.02). We found similar results including studies that enrolled patients within 24 hours after AMI. However, a subgroup analysis that excluded high-risk patients with Killip class III and above showed that β-blockers resulted in a significant reduction in short-term mortality (OR 0.93, 95% CI 0.88–0.99).

Conclusion:

Acute intervention with β-blockers does not result in a statistically significant short-term survival benefit following AMI but may be beneficial for low-risk (Killip class I) patients.

Keywords

acute myocardial infarctionmortalityβ-blockers
Type
State of the Art • À la fine pointe
Information
Canadian Journal of Emergency Medicine , Volume 10 , Issue 3 , May 2008 , pp. 215 - 223
Copyright
Copyright © Canadian Association of Emergency Physicians 2008

References

1.Tu, JV, Austin, PC, Filate, WA, et al. Canadian Cardiovascular Outcomes Research Team (CCORT). Outcomes of acute myocardial infarction in Canada. Can J Cardiol 2003;19:893–901.Google Scholar
2.Herlitz, J, Elmfeldt, D,Hjalmarson, A, et al. Effect of metoprolol on indirect signs of the size and severity of acute myocardial infarction. Am J Cardiol 1983;51:1262–8.Google Scholar
3.Herlitr, J, Emanuelsson, KJ, Swedberg, K, et al. Metoprolol trial: enzyme estimated infarct size. Am J Cardiol 1964;53(suppl): 15D–21D.Google Scholar
4.Yusuf, S, Peto, R, Lewis, J, et al. Beta-blockade during and after myocardial infarction: an overview of the randomized trials. Prog Cardiovasc Dis 1985;27:335–71.CrossRefGoogle ScholarPubMed
5.Freemantle, N, Cleland, J, Young, P, et al. Beta blockade after myocardial infarction: Systematic review and meta regression analysis. BMJ 1999;318:1730–7.CrossRefGoogle ScholarPubMed
6.Woods, KL, Ketley, D, Lowy, A, et al. Beta-blockers and antithrombotic treatment for secondary prevention after myocardial infarction. Towards an understanding of factors influencing clinical practice. The European Secondary Prevention Study Group. Eur Heart J 1998;19:74–9.Google Scholar
7.Chen, ZM, Pan, HC, Chen, YP, et al. COMMIT (ClOpidogrel and Metoprolol in Myocardial Infarction Trial) collaborative group. Early intravenous then oral metoprolol in 45,852 patients with acute myocardial infarction: randomised placebo-controlledtrial. Lancet 2005;366:1622–32.Google Scholar
8.Jadad, AR, Moore, RA, Carroll, D,et al. Assessing the quality of reports of randomized clinical trials: Is blinding necessary? Control Clin Trials 1996;17:1–12.Google Scholar
9.Metoprolol in Acute Myocardial Infarction (MIAMI). A randomized placebo-controlled international trial. the MIAMI trial research group. Eur Heart J 1985;6:199–226.CrossRefGoogle Scholar
10.Randomized trial of intravenous atenolol among 16 027 cases of suspected acute myocardial infarction:ISIS-1. First International Study of Infarct Survival Collaborative Group. Lancet 1986;2:57–66.Google Scholar
11.Wilcox, RG, Rowley, JM, Hampton, JR, et al. Randomized placebo-controlled trial comparing oxprenolol with disopyramide phosphate in immediate treatment of suspected myocardial infarction. Lancet 1980;2:765–9.CrossRefGoogle ScholarPubMed
12.Hjalmarson, A, Herlitz, J, Holmberg, S, et al. The goteborg meto-prolol trial. Effects on mortality and morbidity in acute myocardial infarction. Circulation 1983;67:26–32.Google Scholar
13.Basu, S, Senior, R, Raval, U, et al. Beneficial effects of intravenous and oral carvedilol treatment in acute myocardial infarction. A placebo-controlled, randomized trial. Circulation 1997;96:183–91.Google Scholar
14.Propranolol in acute myocardial infarction. A multicentre trial. Lancet 1966;2:1435–8.Google Scholar
15.Norris, RM, Caughey, DE, Scott, PJ. Trial of propranolol in acute myocardial infarction. BMJ 1968;2:398–400.Google Scholar
16.Andersen, MP, Bechsgaard, P, Frederiksen, J, et al. Effect of alprenolol on mortality among patients with definite or suspected acute myocardial infarction. Preliminary results. Lancet 1979;2:865–8.Google Scholar
17.Wilcox, RG, Roland, JM, Banks, DC, et al. Randomized trial comparing propranolol with atenolol in immediate treatment of suspected myocardial infarction. BMJ 1980;280:885–8.Google Scholar
18.Yusuf, S, Sleight, P, Rossi, P, et al. Reduction in infarct size, arrhythmias and chest pain by early intravenous beta blockade in suspected acute myocardial infarction. Circulation 1983;67:32–41.Google Scholar
19.Norris, RM, Barnaby, PF, Brown, MA, et al. Prevention of ventricular fibrillation during acute myocardial infarction by intravenous propranolol. Lancet 1984;2:883–6.CrossRefGoogle ScholarPubMed
20.Balcon, R, Jewitt, DE, Davies, JPH, et al. A controlled trial of propronalol in acute myocardial infarction. Lancet 1966;2:917–20.Google Scholar
21.Roberts, R, Rogers, WJ, Mueller, HS, et al. Immediate versus deferred beta-blockade following thrombolytic therapy in patients with acute myocardial infarction. Results of the Thrombolysis in Myocardial Infarction (TIMI) II-B Study. Circulation 1991;83:422–37.Google Scholar
22.Clausen, J, Flesby, M, Jorgensen, FS, et al. Absence of prophylactic effect of propranolol in myocardial infarction. Lancet 1966;2:920–4.Google Scholar
23.Evemy, KL, Pentecost, BL. Intravenous and oral practolol in the acute stages of myocardial infarction. Eur J Cardiol 1978;7:391–8.Google ScholarPubMed
24.Salathia, KS, Barber, JM, McIlmoyle, EL, et al. Very early intervention with metoprolol in suspected acute myocardial infarction. Eur Heart J 1985;6:190–8.CrossRefGoogle ScholarPubMed
25.Acute myocardial infarct size reduction by timolol administration. The international collaborative study group. Am J Cardiol 1986;57:28F–33F.Google Scholar