How the heart functions and the basics behind the use of the electrocardiogram to monitor cardiac conduction and evaluate heart disease.

1. WA V E A N D I N T E R V A L C O N C E P T S
EKG TRACINGS

2. WHAT IS AN EKG?
• Noninvasive medical procedure
• Used to monitor the heart’s electrical activity
• Collects information through the use of leads
• Transmits signals to a machine
• Machine creates a tracing

3. EKG TRACING BASICS
• Consists of waves and intervals
• Visual representation of cardiac conduction
• Demonstrates chamber depolarization
• Used to evaluate heart health
• Abnormalities used to identify specific diseases

4. HEART STRUCTURE
• Four total chambers
• Two small chambers known as atria
• Force blood into larger chambers
• Located at the top of the heart
• Two large chambers known as ventricles
• Force blood to the lungs and the body
• Located at the bottom of the heart
• Chambers separated by walls and valves
• Coordinated contraction moves blood in the
proper direction

5. ELECTRICAL CONDUCTION
• Electrical signal causes contraction
• Contractile signal begins in the right atrium
• Travels through atria toward ventricles
• Pace set by nodes
• Travels through ventricles along nerve fibers
• Moves rapidly between cells to ensure that all cells
in a chamber contract together

6. EKG WAVES
• P wave = atrial depolarization
• QRS complex = ventricular depolarization
• T wave = ventricular repolarization
• Cycle repeats 60 – 100 times per minute
• Each cycle is one complete cardiac contraction
• Abnormalities may indicate disease

7. EKG INTERVALS
• Distances between waves
• Used to evaluate conduction
• Most common are PP, RR, QT, QRS
• Waves that are too short or too long may be a sign
of cardiac disease
• Must be evaluated by trained physician

8. ROLE OF THE EKG TECHNICIAN
• Administer electrocardiogram
• Educate patients
• Perform initial quality assessment
• Assist with invasive procedures
• Improve public awareness
• The EKG Technician is an important member of the
medical team who allows facilities to provide
efficient and effective care