All ECG

RAD

Lead I down

Lead II up

Lead III up

LAD

Lead I: up

Lead II: down

Lead III: down

SA block

absent P wave

1° AV block

prolonged PR interval >0.20s

2° AV Block Mobitz I

increasing PR interval until dropped QRS

2° AV Block Mobitz II

Multiple P waves before QRS, ratio

3° AV Block (CHB)

Ps and Qs don’t agree

V Tach

saw blade

R on T PVC

R wave of PVC occurs on T wave

V Fib

squiggly line

RBBB

Two R wave (rR’) V1 and V2

LBBB

Two R waves RR’ V5 and V6, slurred

RAE

tall P wave >2.5mm(0.25mV) LII, LIII, aVF (inferior leads)

LAE

wide P wave >2.5mm(0.1s) LII, LIII, avF

RVH

opposite deflection pattern of QRS in V1 and V5 or V2 and V6

LVH

V1 S wave + V5 R wave ≥ 35 mm

PVC

no p wave, wide QRS, T wave in opposite direction

ST segment depression

ST segment below baseline (downsloping, upsloping, horizontal), ischemia

ST Segment Elevation

ST segment above baseline

MI inferior wall infarction

ST segment elevation in II, III, aVF

MI anterior wall

ST segment elevation

V1, V2, V3, V4

MI lateral wall

ST segment elevation

I, aVL, V5, V6