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34 Cards in this Set

  • Front
  • Back
This Action Potential Phase 0 begins with electrical stimulation
-Interior of cell becomes more + (fast sodium channel)
-contraction of heart (SYST
Return of cell to resting potential
Relaxation of heart (DIASTOLE)
An amplified representation of how action potentials are grouped together to form a pattern or wave
Conduction Pathway of Heart
1) SA node - "the beat" "the boss" 60-100bpm
2) AV node - "gatekeeper" "doorman" 40-60bpm (if SA node fails)
3) AV bundle "bundle of His"
4) Bundle branches
5) Pekinje fibers
*3,4,5) 20-40bpm if SA and AV nodes fail
Blood Pathway through the heart
Deoxygenated blood:

-in through superior vena cava
-R atria
--tricuspid valve
-R ventricle
--pulmonic valve
-pulmonary artery

Oxygenated blood:
--pulmonic veins
-L atrium
--mitral valve
-L ventricle
--aortic valve
EKG Waveform
-starts with SA node and travels through the Atrium
**Atrial Depolarization
**Atrial Contraction
P Wave
EKG waveform:
**Ventricular Depolarization
**Ventricular Contraction
(systole follows)
QRS Complex
EKG waveform:
**Ventricular Repolarization
**Ventricular Relaxation
(diastole follows)
T Wave
Normal value of PR Interval of EKG:
Start of P wave to start of QRS complex "atrial kick"
0.12 - 0.20 secs

*if greater than = problem in AV node
Normal value of QRS Interval:
Electrical conduction through ventricular pathways
0.06 - 0.12 secs

*if greater than = hyperkalemia or problem with bundle branch system
How do you calculate HR on EKG strip
if reg rhythm:
300 / large squares between QRS complexes

if not reg:
# of R waves in 6 sec strip (30 blocks) X 10
EKG Rhythm often seen as a normal variation in athletes, during sleep, or vagal maneuver:
Rate 40-59bpm
P Wave Sinus
QRS Normal
Conduction Normal
Rhythm Regular
Sinus Bradycardia
Treatment for sinus bradycardia
Treat underlying cause

Atropine - anticholinergic, increase HR and dries up

Artificial pacing if patient is hemodynamically compromised
**Pacing Always Ends Danger
Rhythm with:

Rate 101-160bpm
P Wave Sinus
QRS Normal
Conduction Normal
Rhythm Regular
Sinus Tachycardia
Causes of Sinus Tachycardia Rhythm
Increase in epinephrine, dopamine (Catecholamines)
increase in Temp
Decreased fluids
Treatment for Sinus Tachycardia
Treat underlying cause

*Remember increased HR will then lower SV and lower CO to compensate
(CO = HR X SV)
Rhythm with:
Rate 400 - 650bpm
P Wave None **
QRS Normal
Conduction Increased
Rhythm Irregularly
Atrial Fibrillation
- May occur paroxysmally but often becomes chronic
- usually associated with COPD, CHF or other heart disease
Treatment for Atrial Fibrillation
Digoxin, diltiazem (cardizem - calcium channel blocker), other antidysrhythmic meds to control AV conduction rate

Cardioversion - stop rhythm if symptomatic and anticoagulate
**if symptomatic must anticoagulate patient
If AFIB > 48hrs treat with

**anticoagulate first with heparin drip
Rhythm with:

Rate Normal or increased
P Wave Different morphology than sinus due to originates from extopic pacemaker
QRS Normal
Conduction Normal
Rhythm These occur early in cycle and usually do not have a complete compensatory pause
Premature atrial contractions

*occur normally in non-diseased heart but if occur frequently may lead to atrial dysrhythmias
***PAC's don't mean much usually
Rhythm with:
Rate Variable
P Wave usually obscured by QRS or T wave of PVC
QRS < 0.12 secs (Bizarre morphology)
Conduction Impulse originates below the branching portion of the bundle of His
Rhythm Irregular - may occur in singles, couples or triplets; or bigeminy, trigeminy or quadrigeminy
Premature ventricular contractions
-can occur in healthy hearts or in diseased hearts from drug toxicities (digitalis)

***Don't look like normal EKG
Treatment for Premature Ventricular Contractions (PVC's)
**only if:
-associated with acute MI
-occurs as couplets, bigeminy, trigeminy
-frequency >6/min
Rhythm with:
Rate 100-220bpm
P wave Obscured
QRS wide + bizarre morphology
Conduction originates below branches of bundle of His as with PVC's
Rhythm 3 or more ventricular beats in a row (regular or irregular)
Ventricular Tachycardia
(V-Tach) only ventricle contracting
*diseased hearts with CAD, Acute MI, digitalis toxicity, CHF
**often patient symptomatic
***impaired to no cardiac output
Treatment for V-Tach
No - Lidocaine bolus + drip

Yes - Pulse?
Yes: cardioversion + drugs
No: treat as V-Fib
--defibrillation, CPR, drugs
V-Tach with No Pulse Treatment
Shock, Shock, Shock!!!!!!!


Rhythm check
Antirhythmic Meds:
lidocaine, amniodarone
Rhythm with:

Rate None
P wave None
QRS None
Conduction None
Rhythm None
Asystole/Ventricular Stand Still

Treat with CPR, 100% Oxygen, IV, intubate, transcutaneous pacing, epinephrine (1mg IV push Q3-5 mins)
Rhythm with:

Rate Unattainable
P Wave Obscured
QRS Not apparent
Conduction Chaotic electrical activity
Rhythm Chaotic

*absence of cardiac output
*occurs with serious heart disease (Acute MI)
Ventricular Fibrillation (V-Fib)

Treat with:
Immediate defibrillation and ACLS protocols
Identify and treat cause
When something causes a disruption in EKG monitoring
Produced as impulse from SA and AV junction - caused by Atrial contraction
P Wave
Time between atrial depolarization and start of ventricular conduction (depolarization)
P-R interval

Normal = 0.12 - 0.20 secs
Conduction of impulse through the bundle of His to perkinje fibers causing contraction of ventricles
QRS complex

Normal = 0.06 - 0.12 secs
The heart's resting period after ventricles contract
S-T Segment
Ventricular Repolarization
T Wave
5 Steps to assess EKG Strip
1) is there a "P" for every QRST?
2) is rhythm regular? ^----^----^ (msr spaces from r to r)
3) HR (# of Rs in 30 blocks X10 = HR)
4) PR (measure miniblocks)
5) QRS (before Q drops to S)