Left Bundle Branch Block with Less Than 1 mm of Concordant ST Elevation (in the Setting of Hypertrophic Cardiomyopathy)

A male in his 60's with a known history of hypertrophic cardiomyopathy (HOCM) presented for chest pain.  He thought  it was "acid reflux," and it started a few hours prior to his presentation to a non-PCI capable hospital.  He denied any associated symptoms.  His pain was not relieved with NTG.  He had an minimally elevated troponin at the referral institution, (assay unknown).  He was diaphoretic and clutching his chest.  Here is the first ECG:There is sinus rhythm with LBBB and high voltage, and all leads have appropriate and proportional discordance EXCEPT for lead V4, which has less than 1 mm of (inappropriate) concordant ST elevation.  Lead V5 also has significantly less discordance than expected.What should the ECG look like if there is both HOCM and LBBB?  I don't think anyone knows.The patient was transferred to a PCI capable hospital where this ECG was recorded:Now the concordant ST elevation is in lead V5, but since V4 now has a predominantly negative QRS, the difference is a result of lead placement differences between the two ECGs.  V6 has an inappropriately isoelectric ST segment.An ECG from 5 years previous was available:This shows inappropriate concordance of less than 1 mm in V4, and inappropriate isoelectric ST segments in V5, so all this configuration is not new for this patient who has known HOCM.Strictly speaking, none of these meet the first Sgarbossa criterion of 1mm of concordant ST elevation.  In o...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs