Arrhythmia refers to an irregular heartbeat that can be too fast, too slow, or have an extra or missed beat. Arrhythmias are classified as normotopic or ectopic based on whether the sinoatrial node is the pacemaker. Normotopic arrhythmias include sinus arrhythmia, sinus tachycardia, and sinus bradycardia. Ectopic arrhythmias occur when another part of the heart acts as the pacemaker, such as atrial flutter, atrial fibrillation, or ventricular fibrillation. An artificial pacemaker can be implanted to regulate abnormal heart rhythms through electrodes that deliver electrical pulses to the heart.

1. Arrhythmia
Maria idrees; PT

2. DEFINITION
• Arrhythmia refers to irregular heartbeat or
disturbance in the rhythm of heart.
• In arrhythmia, heartbeat may be fast or slow
or there may be an extra beat or a missed
beat.

3. CLASSIFICATION
• In arrhythmia, SA node may or may not be the
pacemaker.
• If SA node is not the pacemaker, any other part of
the heart such as atrial muscle, AV node and
ventricular muscle becomes the pacemaker
• Accordingly, arrhythmia is classified into two
types:
A. Normotopic arrhythmia
B. Ectopic arrhythmia.

4. NORMOTOPIC ARRHYTHMIA
• Normotopic arrhythmia is the irregular
heartbeat, in which SA node is the pacemaker.
• Normotopic arrhythmia is of three types:
1. Sinus arrhythmia
2. Sinus tachycardia
3. Sinus bradycardia.

5. SINUS ARRHYTHMIA
• Sinus arrhythmia is a normal rhythmical
increase and decrease in heart rate, in relation
to respiration.
• It is also called respiratory sinus arrhythmia
(RSA).
• Normal sinus rhythm means the normal
heartbeat with SA node as the pacemaker.
• Heart rate increases during inspiration and
decreases during expiration.

7. SINUS TACHYCARDIA
• Sinus tachycardia is the increase in discharge
of impulses from SA node, resulting in
increase in heart rate.
• Discharge of impulses from SA node is very
rapid and the heart rate increases up to
100/minute and sometimes up to 150/minute

8. Conditions when Sinus Tachycardia
Occurs
Physiological conditions
1. Exercise
2. Emotion
3. High altitude
4. Pregnancy
Pathological conditions
1. Fever
2. Anemia
3. Hyperthyroidism
4. Cardio myopathy
5. Valvular heart disease

9. Features of Sinus Tachycardia
1. Palpitations (sensation of feeling the
heartbeat)
2. Dizziness
3. Fainting
4. Shortness of breath
5. Chest discomfort (angina).

10. SINUS BRADYCARDIA
• Sinus bradycardia is the reduction in discharge
of impulses from SA node resulting in
decrease in heart rate.
• Heart rate is less than 60/minute.

11. Conditions when Sinus Bradycardia
Occurs
Physiological conditions
1. Sleep
2. Athletic heart
Pathological conditions
1. Disease of SA node
2. Hypothermia
3. Hypothyroidism
4. Heart attack
5. Congenital heart disease
6. Atherosclerosis. Bradycardia due to atherosclerosis of
carotid artery, at the region of carotid sinus is called
carotid sinus syndrome.

12. Features of Sinus Bradycardia
1. Sick sinus syndrome
2. Fatigue
3. Weakness
4. Shortness of breath
5. Lack of concentration
6. Difficulty in exercising.
Sick sinus syndrome
• Sick sinus syndrome is the common feature of
sinus bradycardia.
• It is the condition characterized by dizziness and
unconsciousness.

13. ECTOPIC ARRHYTHMIA
• Ectopic arrhythmia is the abnormal heartbeat,
in which one of the structures of heart other
than SA node becomes the pacemaker.
• Impulses produced by these structures are
called ectopic foci.

14. Subtypes of Ectopic Arrhythmia
1. Homotopic arrhythmia, in which the impulses
for heartbeat arise from any part of
conductive system
2. Heterotopic arrhythmia, in which the
impulses arise from the musculature of heart
other than conductive system.

16. ATRIAL FLUTTER
• Atrial flutter is an arrhythmia characterized by
rapid ineffective atrial contractions, caused by
ectopic foci originating from atrial musculature.
• It is often associated with atrial paroxysmal
tachycardia.
• Both the atria beat rapidly like the wings of a
bird, hence the name atrial flutter.
• Atrial rate is about 250 to 350/minute
• Atrial flutter is common in patients suffering from
cardiovascular diseases such as hypertension and
coronary artery disease

17. ATRIAL FIBRILLATION
• Atrial fibrillation is the type of arrhythmia
characterized by rapid and irregular atrial
contractions at the rate of 300 to 400
beats/minute.
• It is mostly due to circus movement of impulses
within atrial musculature
• Atrial fibrillation is common in old people and
patients with heart diseases.
• If it continues for long time, it may cause blood
clot and blockage of blood flow to vital organs.

18. VENTRICULAR FIBRILLATION
• Ventricular fibrillation is the dangerous cardiac
arrhythmia, characterized by rapid and irregular
twitching of ventricles.
• The rate reaches 400 to 500/minute.
• This type of arrhythmia is serious as it leads to
death, since the ventricles cannot pump blood.
• Ventricular fibrillation is very common during
electric shock, coronary occlusion and chloroform
anesthesia ( during cardiac surgeries)

19. ARTIFICIAL PACEMAKER
• Artificial pacemaker is a small electronic device
that is surgically implanted to regulate abnormal
heartbeat.
• It contains a battery powered pulse generator,
that produces electrical impulses capable of
stimulating the heart.
• This pacemaker is implanted under the skin over
the chest of the patient. Pulses generated by this
device are transmitted to the heart through
electrodes.

20. • Electrodes connected to the device are
inserted and passed through a vein and
positioned in the heart chambers.
• The device has a lithium battery that may last
for 10 to 15 years.
• The outer casing of the pacemaker is usually
made of titanium, which is rarely rejected by
body’s immune system.