A modified Sgarbossa criteria can be used to suggested and Myocardial infarct in the presence of a LBBB. Additionally, it has been suggested to look for “Wellen’s signs” in V1-6:
Wellens’ Type A – biphasic pattern of T waves in V leads
Wellens’ Type B – deep negative T wave inversion in V leads
Herzschrittmacherther Elektrophysiol. 2017 Mar;28(1):57-59.
Wellens’ syndrome can indicate high-grade LAD stenosis in case of left bundle branch block.
Modified Sgarbossa Criteria: “best seen in the midprecordial
leads, but may appear in V1–V6”
Sgarbossa A: Concordant ST elevation >1 mm in leads with positive QRS
Sgarbossa B: Concordant ST depression >1 mm in V1–V3
Sgarbossa C: Negative QRS followed by a discordant ST elevation of at least 1 mm
AND 25% of the preceding S.
(The original publication of Sgarbossa et al. stated for Sgarbossa C: ST elevation >5 mm independent of the amplitude of S)
- Findings best seen during period of pain
- at one point only V5 showed Wellen’s.
Comment – had one case that was young with minimal features eventually angiogramed and needed two stents in LAD. Given the LAD occlusions are called the “widow-maker” these measures were lifesaving . Point could be made that a mammary artery bypass would have better longevity…