emDocs - February 15, 2016 - Authors: Santistevan J - Edited by: Koyfman A & Bright J
"TAKE HOME POINTS:
- ST-segment elevation in lead aVR portends a worse prognosis in ACS and often predicts the need for CABG.
- ST-segment elevation in aVR can be caused by any of the following 4 mechanisms:
- LMCA insufficiency
- Very proximal LAD occlusion or complete LMCA occlusion
- Multi-vessel coronary artery disease
- Diffuse subendocardial ischemia
- Patients with complete occlusion of the LMCA often present in cardiogenic shock and require immediate revascularization.
- Patients with NSTEMI and ST elevation ≥ 1mm in aVR are likely to have multi-vessel or LMCA disease and are likely to require CABG, therefore withholding Clopidogrel may be prudent."
emDocs - February 17, 2016 - Authors: Santistevan J - Edited by: Koyfman A & Bright J
"In this post, we are going to review 4 causes of abnormal T-waves:
- Hyperacute T-waves in AMI
- The de Winter T-wave pattern
- Pseudonormalization of T-waves
- Hyperkalemia
TAKE HOME POINTS
- Hyperacute T-waves are often the first manifestation of complete vessel occlusion; they are wide, bulky and prominent.
- Hyperacute T-waves are not necessarily tall, and small T-waves can still be hyperacute when paired with a low-amplitude QRS complex.
- De Winter T-waves represent LAD occlusion (a STEMI equivalent) requiring immediate revascularization.
- Previously inverted T-waves can appear normal and upright in the setting of acute vessel occlusion. This is known as pseudonormalization.
- The tall T-waves associated with hyperkalemia are sharp, pointy, symmetric, and have a narrow base.
- When in doubt, get serial ECGs (every 15 minutes) and use adjunctive information."