ECG (main)

Measurement

• 1 small box = 1mm = 0.04 sec = 40 miliseconds
• 5 small boxes = 1 big box = 5mm = 0.2 sec = 200 miliseconds
• Entire ECG strip is ~10 seconds

Interval	Time (s)	Boxes
PR	0.12 - 0.20	3-5
QRS	.06 - 0.10	1.5-2.5
QTc	<0.44	N/A

Primary Analysis

• ECG Rhythms
• ECG Axis
• Low ECG Voltage

Segments & Intervals

• ST Elevation
• ST Depression
• QT Prolongation

Waves

• Q Waves
• T Waves
• R-wave in V1

Hypertrophy/Enlargement

Cardiac Hypertrophy and Enlargement

• Right atrial enlargement
• Left atrial enlargement
• Left ventricular hypertrophy
• Right ventricular hypertrophy

Bundle and Fascicular Blocks

• Right Bundle Branch Block
• Left Bundle Branch Block
• Left Anterior Fascicular Block
• Left Posterior Fascicular Block

See Also

• ACS - Anatomical Correlation
• ECGs by Diagnosis
• STEMI equivalents