Abnormal EKG Flashcards
Describe the purpose of the delay at the AV node
To optimize ventricular filling
Decribe the plateau during repolarization of the ventricles (ST segment)
Contraction CANNOT occuring during this time
_____1_____ of amoung grouping of EKGs are important because _______2______ across leads can solidify an ______3______.
- Patterns
- Inconsistencies
- Abnormality
_1_ waves tend to be taller in runners due to ___2___ ______3______
- T
- Rapid
- Repolarization
Describe normal sinus rhythm (5)
- Rate 60-100 bpm
- Contains P wave
- QRS for every P wave
- R waves are equidistant
- Contains T wave
Describe sinus arrhythmia (3)
- R waves not equidistant
- More beat to beat variability than normal
- More likely in those with smaller chest walls and narrow AP distance
Describe why it is important that there be beat to beat variability with heart rate.
It indicates that the heart is appropriately adapting to changes in altered thoracic pressure [from breathing]
Describe sinus bradycardia (4)
- Normal in athletes, on beta blockers, with decreased SA node function
- Generally asymptomatic unless pathologic condition exists
- May c/o dizziness, syncope, angina
- Concerning in elderly - decreased contraction force + slow HR = decreased Q, O2 to tissue
Describe sinus tachycardia (3)
- Generally benign, SA node automaticity increased
- T and P wave may be closer together, P wave may be difficult to see
- Pts. asymptomatic
List the causes of sinus tachycardia
- Stress
- Caffeine
- Sleep deprivation
- Pregnancy
- Obesity
- Over training
- Exercise
- Sickness
Describe sinus exit block (2)
- Block in conduction of impulse from SA node to atria
- Pause equal to 2 complete cardiac cycles
Describe Premature atrial contraction (PAC) (4)
- Ectopic focus in either atria initiates and impulse before the next impulse initiated by the SA node
- P wave less rounded, more peaked, comes faster after the T wave [or may be buried]
- Low frequency = asymptomatic; Increased frequency = a-tach or a-fib may result
- Q not effected b/c presence of P wave allowed time for filling
Describe Atrial Tachycardia (4)
AKA supraventricular tachycardia
- HR 100-200 bpm
- P wave may be difficult to define
- Q compromised if prolonged
- Sx include dizziness, fatigue, SOB
List the causes of atrial tachycardia (4)
- PAC
- Pulmonary HTN
- Altered pH
- COPD
Describe atrial flutter (4)
- Rapid rate due to the firing of an ectopic source in the atria
- Q not compromised unless ventricular rate becomes too high
- Extra P waves that have a saw tooth appearance
- Arrhythmia coming from ONE area
List the causes of atrial flutter (8)
- Mitral valve disease
- CAD
- Infarction
- Stress
- Renal failure
- Pericarditis
- Rheumatic heart disease
- MI
Describe atrial fibrillation (6)
- Erratic quivering of atria
- Multiple ectopic foci
- No true depolarization of atria
- AV node acts to control ventricles
- Can’t make out a P wave - not clear and discernable
- At risk for stroke
List the causes of atrial fibrillation (8)
- Advanced age
- CHF
- Ischemia/Infarction
- Cardiomyopathy
- Digoxin toxicity
- Drug use
- Stress/Pain
- Renal Failure
List the problems associated with atrial fibrillation
- No atrial kick [responsible for 30% of Q]
- Ventricular rate < 100 at rest monitor w/exercise for Q compensation
- Ventricular rate > 100 at rest monitor w/all activities and engaged in w/caution
- Likely to have Q decompensation w/ventricular rate > 100
Define RVR
Rapid ventricular rate, > 100 bpm
Describe premature junctional contraction (3)
- P wave missing prior to QRS
- QRS fairly normal
- SA node didn’t fire
Describe junctional escape rhythm (4)
- SA node not functioning properly
- AV junction takes over, ventricular rate 40-60 bpm
- No P waves, QRS a little wider, inverted T wave
- Low Q = dizziness, fatigue, SOB, angina
List the causes for junctional escape rhythm (4)
- Increased vagal tone
- Digoxin toxicity
- Infarction
- Severe ischemia to conduction system (R CAD)
Define unifocal PVC
Arrhythmia coming from one place in the ventricle
Define multifocal PVC
Arrhythmia coming from more than one place in the ventricle
The more PVCs that occur in a row the more _______1______ the __2__
- Compromised
- Q
List the causes of PVCs (9)
- Caffeine
- Nicotine
- Stress
- Overexertion
- Electrolyte imbalance
- Ischemia/Acute Infarction
- Cardiac disease
- CHF
- Overdistention of ventricle
- Chronic lung disease/Hypoxemia
List the name for 2 and 3 beat PVCs
2 = bigeminy
3 = trigeminy
Describe the effect of increased fequency of PVCs (5)
- Filling time of ventricles decreased
- Decreased pre-load, SV, Q
- Dizziness, SOB
- Activity can be compromised, monitor activity
- Can lead to ventricular tachycardia
Describe the effect on Q following any delay in the cardiac cycle
Larger Q following any delay
Describe ventricular tachycardia (4)
- Only QRS waves
- Q and BP greatly diminished
- Sx: light-headedness, syncope, weak thready pulse, disorientation
- Non-shockable, do CPR, will only be upright for 10-15 sec
List the causes of ventricular tachycardia (4)
- Ischemia
- Acute infarction
- Hypertensive heart disease
- Reaction to meds (digoxin)
Describe ventricular fibrillation (4)
- Sequel to ventricular tachycardia
- Life-threatening, emergency
- Shockable rhythm
- Can lead to a-systole
Abnormal rhythm: looks like v-tach, begin close to baseline, gradually increasing and decreasing in a repeating pattern. Medical emergency
Torsades de Pointes
Describe idioventricular rhythm (5)
- 20-40 bpm
- Absent P wave, paced low
- Small R wave
- Probably in lead V1-2
- Not sustainable for life, can cause death
Describe a 1st degree heart block (4)
- Increased PR interval
- Delayed signal at AV nodes
- Normal QRS
- Asymptomatic unless bradycardic
List the causes of 1st degree heart block (3)
- CAD
- Infarction
- Reacting to digoxin
Describe 2nd degree heart block type 1 (3)
AKA Wenckebach
- Benign arrythmia, generally asymptomatic
- Not a QRS for every P wave
- P wave gets longer, longer, skips a beat
List the causes of 2nd degree block type 1 (4)
- Right CAD
- Infarction
- Digoxin toxicity
- Excessive beta blocker
Describe a 2nd degree block type 2 (3)
- Multiple missing QRS complexes
- PR interval normal, P waves punctual/right on time
- Symptomatic when HR is low and Q compromised
List the causes of 2nd degree heart block type 2 (3)
- MI (esp. LAD)
- Ischemia/infarction of AV node
- Digoxin toxicity
Describe 3rd degree heart block (3)
AKA complete block
- Random P, QRS a little wider
- No rhyme or reason to anything
- P and QRS act as 2 independent systems
List the causes of 3rd degree heart block (3)
- Acute MI
- Digoxin toxicity
- Degeneration of conduction system
Describe Pacemaker Rhythms (Ventricular)
A properly functioning pacemaker will show a sharp spike, followed immediately by depolarization of the chamber it is intended to pace.
**Note absence of mappable P waves and sharp spikes followed immediately by wide QRS complexes.