Download Carson ECG presentation

THE CARDIAC CYCLE AND THE
ECG
Carson Vandiver
Einthovens Triangle
The Normal ECG
Sinus Rhythms
• The Impulse is Originating in the SA node
(Sinus Node)
• Characterized by:
– One P wave for Every QRS Complex
– Rhythm is Normally Spaced out Regularly
– PR interval is between .12-.20 Seconds
– QRS is less than .12 Seconds
• Classified by Rate
Normal Sinus Rhythm
Rate is Between 60-100
Sinus Bradycardia
Rate is less than 60 beats per minute
Sinus Tachycardia
Rate is between 100 and 150
Sinus Arrhythmia
Impulse is still originating in SA node but QRS complexes are
spaced out unevenly (Usually related to breathing pattern)
Wandering Atrial Pacemaker
Has all the characteristics of sinus Arrhythmia but P waves have
different Morphology
AV Blocks
• AV blocks means that there is an issue with
the conduction of the Impulse through the
AV node
• Characterized by:
– By an Abnormal PR interval
– Or More than 1 P wave associated with Every
QRS
First Degree AV Block
Impulse is being held for too long at AV Node
Usually Benign (Very Common in Elderly)
Second Degree Type 1 AV Block
PR Interval gets longer until QRS is Dropped
Commonly associated with Myocardial infarctions (Heart Attack) or
infections of the heart such as myocarditis
Second Degree Type 2 AV Block
Impulse is blocked at AV Node
Commonly associated with extensive damage to the bundle branches
usually caused by an anteroseptal Myocardial infarction (heart attack)
Third Degree AV Block
Total disassociation between the electrical activity in the Atria and Ventricles
Very critical requires immediate intervention because they are normally hypotensive
and Bradycardic
Junctional Rhythms
• Av Junction is the secondary pacemaker site for the
heart if the impulse fails to start in the SA node the AV
junction will start firing
• Junctional Rhythms are Characterized by:
– The Absence of a P wave
– Regularly spaced out QRS Complexes
– QRS that is less than .12 seconds in length
• The are classified by Rate
• Can be caused by drug toxicity from Digoxin,
Myocardial infarctions and a number of other
physiological issues
Junctional Escape Rhythm
Rate is 40-60 Beats per Minute
Accelerated Junctional Rhythm
Rate 60-100 Beats per Minute
Junctional Tachycardia
Rate is between 100-150 beats per minute
Atrial Arrhythmias
• Impulse is originating in the SA node
• Characterized by
• QRS that is less than .12 seconds
• Can be benign or life threatening
Atrial Fibrillation (A-Fib)
No organized atrial contraction
Atria is Fibrillating (Pulsating)
Atrial Flutter
Well defined pacemaker within atria firing at a rate of
250-350 times
Suparventricular Tachycardia (SVT)
Occurs when a Pacemaker site develops within the Atria and fires very
quickly (Greater than 150 beats per minute)
Life Threatening
Ventricular Dysthymias
• Caused by a pacemaker site developing
somewhere in the Ventricles
• Characterized by:
– QRS complex that is greater than .12
• Can Be life threatening
Ventricular Tachycardia (V-tach)
Caused by a pacemaker site originating in the ventricles and
beating very fast (100-250 beats per minute)
Life Threatening requires intervention
Cardiac Arrest Rhythms
• With these rhythms the patient does not
have a pulse
• Very life threatening
• If the person does not have a pulse you
should be doing CPR
• Depending on the rhythm these patients
require drugs and defibrillation to correct
Ventricular Fibrillation (V-Fib)
No organized electrical rhythm
Ventricles are Fibrillating (Pulsating)
Pulseless electrical activity (PEA)
The lights are on but no one is home
The heart is still experiencing organized electrical activity but there is no
mechanical activity ie. The person does not have a pulse
Asystole
No electrical activity
Ectopic Beats
• An Ectopic beat is premature heart beat
• They are broken down by the origin of the
electrical impulse
• Most of the time they are benign
Premature Atrial Contraction
Premature Junctional Contraction
A beat originates in the AV Junction early
Premature Ventricular contraction
Bundle Branch Block
There is a block in the transmission of the electrical
impulse somewhere in the ventricles
Can be found within any other rythm
12-Lead ECG
• Much more complicated to read
• Used in the pre-hospital setting to Identify ST
elevation Myocardial Infarctions
• Used in the hospital setting to aid in the
diagnosis various cardiac related conditions
• Uses the 4 limb leads plus 6 precordial leads
to take pictures of the heart from different
angles
12-Lead ECG patches placement
12-Lead ECG