Exam 1: Arrhythmias & ECG Flashcards
Anatomy of the Cardiac Conduction System include
- SA node
- Bachmann’s Bundle
- AV node
- Bundle of His
- Left and Right Bundle Branch
- Purkinje Fibers
Polarization includes
Positive or negative
Types of Polarization include
- Atrial Depolarization
- Ventricular Depolarization
- Ventricular Repolarization
ECG Cardiac Cycle
- P Wave
- PR Interval
- QRS Interval
- ST Segment
- T Wave
- QT Interval
EKG Paper
Time measure in seconds
Amplitude measured in mV
Small box
0.04 secs and 0.1 mV amplitude
Large box
5x5 small boxes = 0.2 secs and 0.5 mV amplitude
Methods of Measuring Rate
- Number of QRS complexes in one minute
- Six second strip
- Number of small boxes between two R waves
- Triplicate method
What are the three types of sinus rhythms?
Normal Sinus Rhythm
Sinus Tachycardia
Sinus Bradycardia
Normal Sinus Rhythm Characteristics
Rate: Normal Duration P Wave: 0.06-0.12 sec P-R interval: 0.12-0.20 sec QRS: <0.12 sec Rhythm: 60-100 bpm
Sinus Tachycardia Characteristics
Rate: Normal Duration P Wave: Normal P-R Interval: Normal QRS: Normal Rhythm: 101-200 bpm
Sinus Bradycardia Characteristics
Rate: Normal Duration P Wave: Normal P-R Interval: Normal QRS: Normal Rhythm: <60 bpm
The four types of Atrial Rhythms include
- Premature Atrial Contraction
- Atrial Flutter
- Atrial Fibrillation
- Supraventricular Tachycardia
Premature Atrial Contraction Characteristics
P Wave: Distorted (d/t ectopic signal travels across the atria by an abnormal pathway) OR hidden by the T-wave
P-R Interval: May be shorter/or longer but still falls w/in normal limits
QRS: Normal <0.12 or Abnormal >0.12
Rhythm: irregular
Atrial Flutter Characteristics
Atrial rate 200-350 bpm & Ventricular rate about 150 bpm
P Wave: Recurring, regular, saw tooth shape waves
P-R Interval: Variable and not measurable.
QRS: Usually normal
Rhythm: Tachydsyrhytmia
Atrial Fibrilation Characteristics
Atrial: 350-600 bpm Ventricular: 60-100 bpm P Wave: Chaotic, fibrillatory waves P-R Interval: Not measurable QRS: Usually normal shape and duration Rhythm: Irregular
Supraventricular Tachycardia Characteristics
Rate: 150-220 bpm P Wave: Often hidden in the preceding T wave P-R: Shorten or normal QRS: Usually normal Rhythm: Regular/slightly irregular
The three types of Ventricular Rhythms include
- Premature Ventricular Contraction
- Ventricular Tachycardia
- Ventricular Fibrillation
Premature Ventricular Contraction Characteristics
Rate: Ectopic focus in the ventricles P Wave: Rarely visible, usually lost in the QRS complex QRS: wide/distorted shape; >0.12 T-Wave: Large and opposite in direction Rhythm: Irregular
Ventricular Tachycardia Characteristics
P Wave: Occurs independently of QRS complex; usually buried in the QRS complex
P-R Interval: Not measurable
QRS: Wide/distorted in appearance; >0.12 sec
T Wave: Opposite direction of QRS complex
Rhythm: Regular or irregular
Ventricular Fibrillation Characteristics
Rate: Not measurable
P Wave: Not measurable
QRS: Not measurable
Rhythm: Irregular and chaotic
AV Block Types
First Degree
Second Degree Type I
Second Degree Type II
Third Degree
First Degree AV Block Characteristics
Rate: HR normal P Wave: Normal P-R interval: PROLONGED >0.20 sec QRS: Shape/duration usually normal Rhythm: Regular (Wife(P Wave) waits for husband(QRS) to come home. He comes home later than normal but he always comes home at the same time each night.)
Second Degree AV Block Type I Characteristics
Rate: Normal, maybe bradycardia P Wave: Normal shape P-R Interval: GRADUAL LENGTHENING QRS: Normal Rhythm: PROGRESSIVE LENGTHENING (Wife(P Wave) waits for husband(QRS) to get home. Each night he comes home later and later, until he doesn’t come home at all.)
Second Degree AV Block Type II Characteristics
P Wave: Normal shape
P-R Interval: Normal or prolonged in duration; remains constant on conducted beats.
QRS: Usually >0.12 d/t bundle branch block.
Rhythm: Atrial = regular, Ventricular = may be irregular.
(Wife(P Wave) waits for her husband(QRS) to come home. Sometimes he comes home, sometimes he doesn’t. But when he does come home, he shows up at the same time each night.)
Third Degree AV Block (Complete Heart Block) Characteristics
P Wave: Normal shape
P-R interval: Variable, no relationship between the P wave and the QRS complex
Rhythm: atrial and ventricular rhythms are regular but unrelated to each other.
(Wife(P Wave) is no longer waiting for her husband(QRS). They are on completely different schedules. There is no longer a relationship)
Cardiac Arrest Rhythms
VT
VF
PEA
Asystole
Common Etiologies of Cardiac Arrest Rhythms
H’s and T’s
C-A-B
Chest compression, Airway, Breathing
C-A-B: Compressions
Should be initiated within 10 second of recognition of arrest
Given at a rate of at least 100/min and each set of 30 compression should take 18 seconds or less.
Depth at least 2 inches for adult, 1/3 of chest for children, 1/3 of chest for infant.
C-A-B: Airway
Cricoid pressure not recommended
C-A-B: Breathing
Briefly check fo no breathing or no normal breathing.
AFTER 30 compressions, the airway is opened then deliver 2 breaths.
AED Automatic External Defibrillator
Children 1-8 years old
Infants <1 year old
SA node
Start of impulse
Dominant stimulator
Sends impulse all throughout the atrium -> atrium contraction
Distance from SA to AV node allows
Emptying of the atrium
Bundle of His
Separates into right and left ventricles
Time to get bundle of his allows filling of ventricles
Purkinje Fibers
Stimulates ventricles to contract -> CO
Vagus Nerve
Decreases firing of SA node
Depolarization
Contraction