Dawn has reviewed the basic ECG findings in today’s case — including the
presentation of epigastric pain (not chest pain) of 3 hours duration in this 63-year old
man with risk factors and a long history of “non-compliance” to medical treatment. As
per Dawn — there is diffuse ST depression with ST elevation in lead aVR greater than
in lead V1 — which is an ECG pattern consistent with DSI (Diffuse Subendocardial
Ischemia). Cath results in today’s case confirm that this patient had severe, diffuse
coronary disease as the cause.

I’ll add a few points to Dawn’s excellent discussion:

POINT #1: It’s important to remember that DSI may be caused by entities other than
severe coronary disease (with or without cardiogenic shock). Examples of other entities
that may cause an ECG pattern of DSI include sustained tachyarrhythmias (SVTs or
VTs) — profound hypotension — GI bleeding — anemia — and others (Please check
out ECG Blog #250 for more on this pattern of DSI — https://tinyurl.com/KG-Blog-250 ).

POINT #2: With a “pure” ECG picture of DSI from severe coronary disease — the
patient does not have acute coronary occlusion. Instead — they simply have severe
coronary disease, but with patent vessels. This point is commonly misunderstood. Also
poorly appreciated — is that the “numbers” for the degree of coronary narrowing do
NOT always tell the whole story — as during the course of acute coronary occlusion,
the “culprit” vessel may sometimes occlude — then spontaneously open — then
reocclude, going through this process sometimes multiple times until there is finally a
stabilization of the event. We have NO idea from the limited history here if this might be
a possibility (ie, We just don’t know if any of the coronary narrowings mentioned here
were at some recent time completely occluded … ).

POINT #3: Although true that there is diffuse ST depression in 9/12 leads (with ST
elevation in lead aVR>V1) — this ST depression is MAXIMAL between leads V2-thru-
V4, in which there are biphasic T waves with terminal positivity. The “shape” of the ST
depression in these leads suggests a positive “Mirror Test” — with this localization (ie, of
clearly maximal ST depression between leads V2-to-V4) — suggests that in addition to
diffuse coronary disease — there may also be acute posterior MI.

POINT #4: Isn’t it “strange” — that lead III shows a flat ST segment and a different
“shape” of T wave inversion than is seen in the other inferior leads. This is because
today’s ECG has elements suggestive of Aslanger’s Pattern, in which the patient has
severe, diffuse coronary disease in association with acute/recent inferior infarction
(Please check out ECG Blog #322 https://tinyurl.com/KG-Blog-322 — for more on
Aslanger’s Pattern).

Alas, not all patients read the textbook — and especially in today’s patient known for his
poor compliance with medical treatment — it is anyone’s guess as to what happened
when in terms of prior, recent and/or acute cardiac events. What we DO know — is
given the history of severe chest pain and this ECG — that immediate cardiac cath was
essential!