Sgargossa criteria

In 1996, Sgarbossa described the Sgarbossa criteria named after him, with the help of which a myocardial infarction can be detected even in a left bundle branch block with a history of myocardial infarction. These criteria were modified by Smith in 2012 (Sgarbossa 1996 / Smith 2012).

A myocardial infarction (MI) with ST elevation(STEMI) is difficult to detect in a previously existing left bundle branch block or ventricularly stimulated rhythm. Sgarbossa et al. therefore examined 262 patients with left bundle branch block in a retrospective study, in each of whom 131 cases had had an MI or no MI (Simon 2017).

The found criteria are added to a respective score:

• Sgarbossa A: A concordant (same direction as the QRS complex with positive QRS) ST- elevation of ≥ 1 mm in at least one derivation (5 points)
• Sgarbossa B: there is a concordant ST depression of at least 1 mm in ≥ 1 Derivation of V1, V2 or V3 (3 points)
• Sgarbossa C: An elevation of the ST section of ≥ 5 mm in a derivation with simultaneously discordant deflection direction in the area of the QRS complex (2 points) (Jahn 2019)

A reasonably reliable statement can be made from a value of ≥ 3 points. A meta-analysis of 10 studies showed a specificity of 98 % and a sensitivity of 20 % (Simon 2017).

Somewhat more exact statements can be made with the modified Sgarbossa criteria according to Smith. The criteria Sgarbossa A and B were retained, Sgarbossa C modified:

There is at least one elevation of the unconformant ST- line of ≥ 1 mm, provided that ≥ measures 25% of the preceding S- wave (Gotthardt 2018).

Note: However, if the Sgarbossa criteria are not present, an infarction cannot be excluded.

1. Gotthardt P et al (2018) Correction: STEMI equivalents and high-risk NSTEMIs . Emergency and rescue medicine . (21) 142 Springer Link https://doi.org/10.1007/s10049-018-0412-0
2. Jahn M et al. (2019) EKG for Emergency Medical Services. Elsevier 129
3. Sgarbossa E B et al (1996) 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. 334 (8): 481 - 487
4. Simon A et al (2017) Right bundle branch block, left bundle branch block, pacemaker in acute coronary syndrome - can we forget the ECG here? The ischemic ECG: frequent dilemma in the emergency department: myocardial infarction with left bundle branch block. Dtsch med Wochenschr 142 (17) 1324 - 1325
5. Smith S W et al (2012) 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. Annals of Emergency Medicine 60 (6) 766 - 776