This is the recap and conclusion for the previous case:
Hereâ€™s the initial 12 lead ECG:
What do we see?
– Sinus rhythm with 1Left Atrial Abnormality or â€œEnlargementâ€
– Wide complex QRS with a Right Ventricular Conduction Delay pattern or Right Bundle Branch Block (RBBB) morphology seen as rSRâ€™ in V1 but abnormal S waves for a typical RBBB, therefore, Intraventricular Conduction Delay (IVCD).
– Pathologic leftward frontal (limb leads) axis >-30 degrees (negative QRS in lead II) with two posibilities:
. Left Anterior Fascicular Block (LAFB)
. Left Ventricular Hypertrophy (LVH)
– Generalized ST segment depression
– ST segment elevation in aVR
There were 3 main causes suspected by most healthcare providers:
- Proximal LAD Occlusion
- Left Main Coronary Artery Occlusion
- 3 vessel disease
Bottom line:Â DIFFUSEÂ SUBENDOCARDIAL ISCHEMIA
Now, some sources believe that elevation in aVR with generalized ST segment depression, a.k.a.Â Non-STEMI,Â indicate Left Main occlusion, however, in reality,Â the actual finding of a thrombus occluded Left Main artery is NOT that common.
Cases with these findings are more commonly the result of :
- multi-vessel disease
- severe atherosclerosis
- catecholamine induced vasospasm
Either way, this is a STEMI equivalent which requires further investigationâ€¦
Based on the initial complaint of chest heaviness + vomiting, both being Acute Coronary Syndrome (ACS) signs, the patient was given 324 mg ASA and two repeated doses of .4 mg NTG tablet sublingual in a 5 minute interval. A serial 12 lead ECGs were obtained during transport:
The patient was treated with a total of 4 NTG tablets, 1â€³ NTG paste on left chest wall and 4mg Zofran. Upon arrival to the initial receiving facility, the chest heaviness had decreased to 1/10 level and improved general appearance.
One last pre-hospital 12 lead ECG was obtained:
- No thrombus (no occlusion)
- Coronary Artery Disease (CAD) and severe stenosis
- 100% Mid Left Anterior Descending (LAD) blockage
- 75% Right Coronary Artery (RCA) blockage
- 50% Distal LAD blockage
- Troponin I = .07 ng/mL (.40-2.10 ng/mL normal range)
- Creatine = 1.6 mg/dL (.10-9.0 mg/dL)
The patient was found to be with reduced Ejection Fraction (EF) of 35% during the initial hospitalization and was placed on Intra-aortic Balloon Pump at a 1:1 systolic ratio with improved EF of 50%.
The patient was transferred the next morning to a higher level of care facility for Coronary Artery Bypass Graft (CABG) consult. During transport, the patient was on a Heparin drip at 1000 U/hr and NTG drip at 10 mcg/min. This 12 lead ECG was obtained prior transport:
CAD and severe stenosis are more common causes of Subendocardial Ischemia rather than an active occlusion of the Left Main Coronary Artery, which usually present with generalized ST segment elevation and patients often do not survive due to extensive Myocardial Infarct.