|
|
Arrhythmia
See Also:
Arrhythmia:
Introduction & Overview
Arrhythmia: Types
Arrhythmia:
Causes & Risk Factors
Arrhythmia: Signs
& Symptoms
Arrhythmia:
Medical Tests & Diagnosis Methods
Arrhythmia:
Treatment & Prevention Options
Types of Arrhythmias
Arrhythmia can be broadly classified
into two types, based on the speed of heart rate:
- Tachycardia: Heart beat is regular (i.e., sinus
rhythm) but the rate is more than 100 beats per
minute.
- Bradycardia: Heart beat is regular (i.e., sinus
rhythm) but the rate is less than 60 beats per
minute. (5)
Ecotopic Beats are a third type and
are extra heartbeats which are very common. Ecotopic
beats are usually not dangerous and do not damage the
heart (6).
Further arrhythmias are categorized
based on their origin in the heart.
1. Atrial arrhythmias:
Arrhythmias originating in atria are as follows:
Atrial
Fibrillation: In this type, the
heart’s electrical signals lose their
regular pattern and the heart’s atria (upper
two chambers) start emitting uncoordinated
electrical signals. The atria pump the blood at a
faster and uneven rate without contracting fully.
The heart may contract 5-7 times faster than
normal i.e., about 300-400 beats per minute.
Atrial fibrillation is not life threatening but
can lead to rhythm problems, chronic fatigue,
congestive heart failure and in worst cases, a
stroke. It is important to note that electrical
signals originate in a different part of the
atrium other than the sinoatrial node.
Supraventricular
Tachycardia (SVT) or Paroxysmal Supraventricular
Tachycardia (PSVT): Supraventricular
tachycardia involves both the atria and the
ventricles. This type of tachycardia originates
either in the atria or in the middle region.
Atrial
Flutter: This is similar to atrial
fibrillation but for the electrical signals
spreading through the atria in a fast and
irregular rhythm. The key difference being that
in atrial flutter is the electrical impulses are
more organized and more rhythmic as compared to
that in atrial fibrillation.
Premature
Atrial Contraction (PAC): In this type,
premature beats or extra beats cause irregular
heart rhythms which start in the atria. They are
very common in normal children and teenagers.
Sick
Sinus Syndrome: The heart rate slows
down when the sinoatrial node does not fire the
signals properly and the heart rate may switch
between a slow rate (Bradycardia) and a fast rate
(tachycardia).
Sinus
Arrhythmia: Cyclic changes in heart rate
during breathing are called sinus arrhythmia.
Sinus
Tachycardia: In this type, a normal
increase in the heart rate occurs due to fever,
excitement and exercise leading to passage of
electric signals at a faster pace than usual.
Wolff-Parkinson-White
(WPW) Syndrome: Abnormal pathways
between the atria and ventricles cause the
electrical signals to move speedily from atria to
ventricles and bounce back leading to very fast
heart rates (4) & (7).
2. Ventricular arrhythmias:
Arrhythmias originating in ventricles are fatal and
require immediate medical attention.
Ventricular
Tachycardia (VT): Ventricular
tachycardia involves only the ventricles and
originates in the ventricles. VT is a fast
regular beating of the heart that last a few
seconds or longer.
Premature
Ventricular Contraction (PVC): PVCs
originate in the ventricles causing irregular
heart rhythms. PVCs are very common in normal
children and teenagers.
Ventricular
Fibrillation: Disordered electrical
activity causes ventricular fibrillation leading
to rapid, unsynchronized and uncoordinated
contraction of the heart. Little or no blood is
pumped by the heart during ventricular
fibrillation resulting in collapse or even sudden
death of the patient (4) & (8).
3. Bradycardia: Bradycardia
can be classified into following types:
Heart
Block or Atrioventricular (AV) block: It
is the blockage of electrical signals from the
atria to the ventricles causing abnormal slowing
down of contractions. Heartblockage can be
further classified as first degree, second degree
or third degree (complete).
Bundle
block branch: Bundles involved can be
either left or right bundles that could be
blocked from transmitting heart signals to the
ventricles. Left bundle branch block (LBBB) is
further classified as complete or partial
(anterior fascicular block or posterior
fascicular block). Right bundle branch block
(RBBB) is also similarly classified as partial or
complete. Other types of bundle branch block are
bifascicular block and trifascicular block (2).
See Also:
Arrhythmia:
Introduction & Overview
Arrhythmia: Types
Arrhythmia:
Causes & Risk Factors
Arrhythmia: Signs
& Symptoms
Arrhythmia:
Medical Tests & Diagnosis Methods
Arrhythmia:
Treatment & Prevention Options
Article by Kona Vishnu, MS
Medical Writer,
OmniMedicalSearch.com
|
|
