Arrhythmias are abnormalities in the heart's rhythm or electrical system. There are two main features of arrhythmias - the site of origin within the heart and the effect on heart rate. Common types include atrial fibrillation, ventricular tachycardia, and ventricular fibrillation. Atrial fibrillation causes the atria to quiver chaotically instead of rhythmically and can lead to blood clots. Ventricular tachycardia and ventricular fibrillation involve abnormal electrical signals from the ventricles and are more serious, as they can be fatal if not treated immediately.

1. Arrhythmia Basics
Presentation by Mary Burns Prine, MA

2. Normal Heart Behavior
• Heart Rate between 60 –
80
• Begins with electrical
signal in upper right part of
heart (sinus node)
• Sinus node is heart’s
pacemaker

3. Heart’s electrical system
Electrical impulse begins at sinus node. Impulse stimulates the
heartbeat through the heart.

4. Two features of arrhythmias
• Site of origin
– Atria
– Atrioventricular node (AV node)
– Ventricles
• Affect on heart rate
– Too slow heart rate
(bradycardia)
– Too fast heart rate
(tachycardia)

5. Common types of Arrhythmia
• Atrial Fibrillation
• Ventricular tachycardia
• Ventricular Fibrillation

6. Atrial Fibrillation
• Common! About 1 in 4 over 40 years old
• Atria quiver (fibrillate) chaotically instead
of rhythmically
• Blood not circulated efficiently
• Symptoms: weakness, shortness of
breath, lightheadedness, palpitations &
chest pain
• CAN LEAD TO BLOOD CLOTS!

7. Atrial Fibrillation

8. Ventricular Tachycardia & Ventricular Fibrillation
• More serious
• Caused by abnormal electrical signals from
ventricles
• Can develop during heart attack or months after
from damaged heart

9. Ventricular Tachycardia
Tachycardia: Heart rate over 100 bpm. Can cause
palpitations, light headedness, dizziness, weakness,
fainting and drop in blood pressure. Can survive for
hours without treatment BUT can progress to Ventricular
fibrillation which is fatal.

10. Ventricular Fibrillation
• Ventricles twitch rapidly & chaotically,
unable to pump blood
• Can lead to death if not treated within a
few moments

11. Symptoms of Ventricular Fibrillation
Loss of consciousness or fainting is the most common sign
of ventricular fibrillation.
Early ventricular fibrillation symptoms (may start up to
an hour before ventricular fibrillation & fainting):
– Chest pain
– Rapid heartbeat (tachycardia)
– Dizziness
– Nausea
– Shortness of breath

12. Treating Fibrillation
• CALL 911 IMMEDIATELY!
• Use Automated External Defibrillator if
available (AED) OR
• Begin chest compressions (100/minute)