12 Lead EKG Interpretation and STEMI Mimics

Raymond L. Fowler, MD, FACEP

Professor and Chief Division of Emergency Medical Services

Department of Emergency Medicine UT Southwestern Medical Center

Augustus Waller

1887

Einthoven

Netherlands – ECG 1895

Einthoven

String Galvanometer

Einthoven

Lead I

Lead II Lead III

+ +

+

PQRST

Lead I

Lead II Lead II

+ +

+ Augmented Voltage Leads

avF

avL avR

Added by Goldberger

in 1942

V1 V2 V3 V4

V5

V6

V Leads added by AHA and the Cardiac Society of Great Britain 1938

aVR

RHYTHM STRIP INTERPRETATION

vs. 12 LEAD INTERPRETATION

Rate

Rhythm

Axis

Hypertrophy

Infarction

P

Intervals (PR QRS QT)

ST

T

U

Assessment

R-R-P-I-ST-T-U-A

Concave upwards is probably

early repolarization

Convex upwards is an injury pattern, meaning infarction

Let’s Practice!

Acute Inferoposterior Myocardial Infarction

Acute Posterolateral Wall Myocardial Infarction

Acute Inferoposterolateral MI

Acute Anterolateral Myocardial Infarction

Acute Anterolateral Myocardial Infarction

Acute Anterolateral Myocardial Infarction

Benign Early Repolarization (BER)

Early Repolarization vs MI

Acute Pericarditis

BER vs. Acute Pericarditis

Frequent Ectopy

PUT ON THE PACING PADS!!

PUT ON THE PACING PADS!!

Left Bundle Branch Block

Left Ventricular Hypertrophy with repolarization abnormality

Brugada

Bifascicular Block with Acute Anteroseptal MI

Mobitz II converting to sinus

Put on the Pacing Pads!!!

Block Degree: All, Some, or None Type: Where is the block?

Ratio: P’s to QRS’s

Speaking of Paced Rhythms

Acute Hyperkalemia

Prompt and accurate analysis of the ECG requires

anatomical understanding and continual practice

Mattu: “It is your BEST test!!”

ECG Interpretation Skills Have to be

Maintained

Promise yourself (and your patients)

that a lifetime of continual study and refresher courses will accompany your practice