Embed Size (px)
Citation preview
12-Lead Electrocardiography
a comprehensive course
Adam Thompson, EMT-P, A.S.
The
Precordial
Axis
Frontal Axis
Precordial Axis
• Sometimes called Z axis• Clockwise or Counterclockwise rotation
Precordial AxisFrontal Plane Axis Precordial Axis
ERAD-90 to 180
Right Axis Deviation90 to 180
Pathological Left Axis Deviation
-30 to -90
Early TransitionCounterclockwise
Rotation
Late TransitionClockwise Rotation
• Ventricular Rhythm• Paced Rhythm• Dextrocardia• Electrolyte derangement
• May be normal• LPFB• Pulmonary disease• RVH• RBBB• WPW• Dextrocardia•Venrticular Rhythm
• Pregnancy• LAFB• WPW• Pulmonary disease• LBBB• Hyperkalemia• Q-waves, MI
• Posterior wall infarction• RVH• RBBB• WPW
• Sometimes Normal, especially in women• Anterior MI• LVH• LAFB• LBBB• Lung Disease
Precordial Axis
Precordial Leads = V Leads
Sometimes called Chest Leads
Precordial Axis
• The main impulse travels down then to the left.
1
3
22
3
4
Mean vector
Cardiac vector
Precordial Axis
1
3
22
3
4
Mean vector
Cardiac vector
V1 V2
V3V4 V5
V6
Precordial Axis
• The normal transition zone is between V3 and V4.
• V1 should be predominately negative.• V6 should be mostly positive.
Precordial Axis
Lets take a look at a 12-lead
Precordial Axis
Is V1 mostly negative?
Precordial Axis
Is V6 mostly positive?
Precordial Axis
Where is the transition?
Precordial Axis
The Precordial Axis is Normal
Precordial Axis
Now picture the precordial leads in this pattern.
V1
V2
V3
V4
V5V6
Precordial Axis
V1
V2
V3
V4
V5V6
Normal transition
Precordial Axis
V1
V2
V3
V4
V5V6
Early transition = Counterclockwise Rotation
Precordial Axis
V1
V2
V3
V4
V5V6
Late transition = Clockwise Rotation
Precordial Axis
Precordial Axis
Early Transition - Counterclockwise Rotation
Precordial Axis
Early Transition - Counterclockwise Rotation
Precordial Axis
Another Example
Precordial Axis
Late Transition - Clockwise Rotation
Precordial AxisFrontal Plane Axis Precordial Axis
ERAD-90 to 180
Right Axis Deviation90 to 180
Pathological Left Axis Deviation
-30 to -90
Early TransitionCounterclockwise
Rotation
Late TransitionClockwise Rotation
• Ventricular Rhythm• Paced Rhythm• Dextrocardia• Electrolyte derangement
• May be normal• LPFB• Pulmonary disease• RVH• RBBB• WPW• Dextrocardia•Venrticular Rhythm
• Pregnancy• LAFB• WPW• Pulmonary disease• LBBB• Hyperkalemia• Q-waves, MI
• Posterior wall infarction• RVH• RBBB• WPW
• Sometimes Normal, especially in women• Anterior MI• LVH• LAFB• LBBB• Lung Disease
Precordial AxisNormal R-wave progression
Precordial AxisEarly R-wave progression
Precordial AxisLate R-wave progression
Bundle Branch Blocks
1
2
3
Left Bundle Branch Block
V1
Bundle Branch Blocks
1
2
3
Right Bundle Branch Block
V1
Bundle Branch Blocks
V1
V1
Bundle Branch Blocks
= RBBB
= LBBB
V1
V1
GT
RBBB Morphologies
LBBB Morphologies
Bundle Branch BlocksFrontal Plane Axis Precordial Axis
ERAD-90 to 180
Right Axis Deviation90 to 180
Pathological Left Axis Deviation
-30 to -90
Early TransitionCounterclockwise
Rotation
Late TransitionClockwise Rotation
• Ventricular Rhythm• Paced Rhythm• Dextrocardia• Electrolyte derangement
• May be normal• LPFB• Pulmonary disease• RVH• RBBB• WPW• Dextrocardia•Venrticular Rhythm
• Pregnancy• LAFB• WPW• Pulmonary disease• LBBB• Hyperkalemia• Q-waves, MI
• Posterior wall infarction• RVH• RBBB• WPW
• Sometimes Normal, especially in women• Anterior MI• LVH• LAFB• LBBB• Lung Disease
Bundle Branch Blocks
Bundle Branch Blocks
The End
“Its finally over”
…Well almost.
More to come in lesson three.
