Sgarbossa’s Criteria for Acute MI in Left Bundle Branch Block

– share this tool –

Clinical Use

Assess likelihood of acute myocardial infarction in patient with chest pain and baseline left bundle branch block (LBBB)

More Info

Sgarbossa’s Criteria1 derived from a cohort of 26,003 North American patients. Three ECG criteria with independent value in the diagnosis of acute myocardial infarction in patients with prior left bundle branch block are used.

ECG Finding Score
Concordant ST elevation >1 mm in leads with upward QRS 5
Concordant ST depression > 1 mm in V1-V3 3
Discordant ST elevation > 5 mm in leads with downward QRS 2


Sgarbossa’s Criteria are specific, but not sensitive for diagnosing acute myocardial infarction.

≥3 points – specificity of ≥90%, sensitivity as low as 36%


Modified Sgarbossa’s Criteria by Stephen Smith2 as follows:

1) Changing the 3rd component to be ST elevation OR depression discordant with the QRS complex and with a magnitude of ≥25% of the QRS complex.

2) Unweighted. It is positive if at least 1 component is met.

Modified Sgarbossa’s Rule – specificity of 88%, sensitivity 100%


1 Sgarbossa EB, Pinski SL, Barbagelata A, Underwood DA, Gates KB, Topol EJ, Califf RM, Wagner GS. Electrocardiographic diagnosis of evolving acute myocardial infarction in the presence of left bundle-branch block. GUSTO-1 (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) Investigators. N Engl J Med. 1996 Feb 22;334(8):481-7. Erratum in: N Engl J Med 1996 Apr 4;334(14):931. PubMed PMID: 8559200. Full Text
2 Smith SW, Dodd KW, Henry TD, Dvorak DM, Pearce LA. Diagnosis of ST-elevation myocardial infarction in the presence of left bundle branch block with the ST-elevation to S-wave ratio in a modified Sgarbossa rule. Ann Emerg Med. 2012 Dec;60(6):766-76. doi: 10.1016/j.annemergmed.2012.07.119. Epub 2012 Aug 31. Erratum in: Ann Emerg Med. 2013 Oct;62(4):302. PubMed PMID: 22939607. Full Text


We are doing our best to prepare the content of this website. However, Cardiology Connections, Corp cannot warranty the expressions and suggestions of the contents, as well as its accuracy. In addition, to the extent permitted by the law, Cardiology Connections, Corp shall not be responsible for any losses and/or damages due to the usage of the information on our website. Furthermore, the links contained on our website may lead to external sites, which are provided for convenience only. Any information or statements that appeared in these sites are not sponsored, endorsed, or otherwise approved by Cardiology Connections, Corp. For these external sites, Cardiology Connections, Corp cannot be held liable for the availability of, or the content located on or through it. Plus, any losses or damages occurred from using these contents or the internet generally.

Developer & Illustrator: Sirikarn Napan, MD, FACC