LBBB: Using the (Smith) Modified Sgarbossa Criteria would have saved this man ' s life

Case submitted and written by Dr. Jesse McLaren (@ECGcases), ofEmergency Medicine CasesReviewed by Pendell Meyers and Steve SmithAn 85yo with a history of hypertension developed chest pain and collapsed, and had bystander CPR. The paramedics found the patient with ROSC and a GCS 7, and an ECG showing LBBB with possible lateral ST elevation. The patient was brought to the ED as a possible Code STEMI and was seen directly by cardiology. On arrival, GCS was 13 and the patient complained of ongoing chest pain. Vitals were HR 58 BP 167/70 R20 sat 96%. Below is the first ED ECG, labeled LBBB by the machine. Are there any indications to activate the cath lab?There is sinus rhythm, LBBB and disproportionately discordant STE in V4 (ST/S = 2/6 = 0.33) that meets the Modified Sgarbossa Criteria. There is also a hint of concordant STE in V5 but it might be less than 1mm. There is also a hint of concordant STE in III.In III, there is slightly less than 1 mm STE in the context of an isoelectric QRS. In LBBB, when the QRS is isoelectric (neither positive nor negative), the ST segment should also be isoelectric. 1 mm of STE here is highly suggestive of OMI.Lead aVL has at least 1 mm of reciprocal STD in the context of a QRS which is under 4 mm. Thus, there is nearly 30% discordant STD, which is very specific for OMI (see both the derivation and the validation of Smith Modified Sgarbossa criteria - see validation results below).  According to the validation of the Modified Sgarbossa...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs