EKG Interpretation

RATE

• 300, 150, 100, 75, 60, 50
• For bradycardia & irregular rhythms: rate = cycles/6 sec. strip ✕ 10

RHYTHM (arrhythmias, tachyarrhythmias, conduction blocks)

• P before each QRS.
• QRS after each P.
• PR intervals (for AV Blocks).
• QRS interval (for BBB).
• If Axis Deviation, rule out Hemiblock.

AXIS

• QRS above or below baseline for Axis Quadrant (for Normal vs. R. or L. Axis Deviation).
• For Axis in degrees, find isoelectric QRS in a limb lead of Axis Quadrant using the “Axis in Degrees” chart.
• Axis rotation in the horizontal plane: (chest leads) find “transitional” (isoelectric) QRS.

HYPERTROPHY

• In V1
• P wave for atrial hypertrophy.
• R wave for Right Ventricular Hypertrophy.
• S wave depth in V1…
• + R wave height in V5 for Left Ventricular Hypertrophy.

INFARCTION

• Scan all leads for:
• Q waves
• Inverted T waves
• ST segment elevation or depression
• Find the location of the pathology, and then identify the occluded coronary artery.