Johnston ECG Rhythms and Disturbances Flashcards
What is a normal axis considered?
- AVF positive and lead 1 positive
- bottom right quadrant
Left axis?
- Positive lead 1
- Negative AVF
- Top right quadrant
Right axis?
- negaitve lead 1
- positive AVF
- bottom left quadrant
rate rhythm axis
- 100 bpm
- Left axis
- positive lead 1 negative AVF
- sinus rhythm tachy
Symptoms of arrhythmia?
- Palpitations such as skipping, pounding, irregular
- Lightheadedness
- Syncope
- Chest pain
- Dyspnea
- Sudden death
Etiology for arrhythhmia?
- Stress
- Ischemia
- Hypoxia
- Metabolic acidosis
- Infection
- Inflammation
- Cardiomyopathy
- Electrolyte imbalance
- Drugs
- Htn
What is sinus tachycardia?
- physiologic/pathologic process
- can be caused by emotion, anxiety, fear, drugs, hyperthyroidism, fever, pregnancy, anemia, CHF
- Hypovolemia
- Treat underlying cause
what is this
normal sinus rhythm with physiologic sinus arrhythmia
what is this and what is rate
all are sinus tachycardia
- 138 bpm
- 160 bpm
- 140 bpm
What is considered bradycardia?
<60bpm
Where are you going to see sinus bradycardia?
- Normal people
- Healthy athlete
- Physiologic component to sleep, fright, carotid sinus massage/hypersensitivity
- Obstructive jaundice
- Sliding hiatal hernia
- Valsalva maneuver
What type of drugs can cause bradycardia?
Beta blockers such as propanolol and metoprolol
Medical conditions/situations associated with bradycardia? (labs)
- Acute inferior MI (increased vagal tone, N/V)
- Ischemia
- decreased pO2
- Increased pCO2
- Decrease PH
- Increase BP
- Sick Sinus Syndrome
what is this?
sinus bradycardia
How do you treat sinus bradycardia?
- Depends on clinical setting and cause
- it may not need to be treated
- Depends on hemodynamics
- Use Atropine
What is automaticity?
- Property of cardiac cell to depolarize spontaneously during phase 4 action potential leads to generation of an impulse
What is the significance of premature atrial contractions?
- can feel it or see it on ECG but it is of no hemodynamic significance
- unless it turns into a lot of irregular beats or causes distress
When can you see a PAC?
- Absence of significant heart disease
- associated with stress alcohol tobacco coffee COPD and CAD
what is this?
PAC
what is this?
non conductive PAC
Different types of PAC
Treatment of PACs?
- treat cause
- Beta adrenergic antagonist
- Metoprolol 25-50 mg BID-TID
What is paroxysmal atrial tachycardia?
- Sudden heart rate greater than 100 BPM
- look for irritable focus P wave
- This one is about 150-200 bpm
PAT with AV block
- think digitalis excess or toxicity
- ratio of 2:1 P:QRS
What is multifocal atrial tachycardia?
- 3 or more P waves
- PR interval varies
- Irregular ventricular rhythm
- Atrial rate >00 bmp
- Associated with an underlying pulmonary disease
What is this?
MAT
3 or more different types of atrial contractions (look at P )
what is this?
- Multifocal Atrial Tachy
- biphasic
- decreased amplitude
- inverted (#4)
How do you treat MAT?
- Ca channel blocker
- Diltiazem
- Verapamil
- Mg SO4
- amiodarone
- digitalis isn’t helpful and DC cardioconversion isn’t effective
What is A fib?
- Atrial quivering with a rate of 350-600 bpm
- Undulating baselines, no discernible P waves
- Irregular PR intervals
- Irregularly irregular
what is this
- A fib
- can’t make out any P waves at the arrows, just see undulation of the baseline
what is seen?
a fib
What has a typical “saw tooth pattern”
- Atrial flutter: 250-350 bpm
- Seen best on leads II, III, AVF, and V
What is paroxysmal junctional tachycardia?
- 150-250 bpm
- P wave may be lost in QRS, inverted before or after each QRS
- Comes from the junction UP to the atrium (that is why P wave is inverted)
what is happening?
P wave is buried in QRS or ST segment, it is a paraxysmal junctional tachycardia as it is irritable junctional focus paces rapid
what is this?
- QRS is narrow and rate is around 200
- Junctional tachycardia
What is this?
- Paroxysmal Supraventricular Tachycardia
- includes PAT and PJT
What causes Premature Ventricular Contractions (PVC’s)
- normal heart
- CAD MI HF MI Hypoxia
- Valvular heart disease
- Congenital heart disease
- Cardiomyopathy
- Acid base imbalance
- Hyperthyroid
ECG characteristics of PVC’s?
- premature bizarre wide QRS
- No preceding P wave, may produce a retrograde P wave in ST segment
- ST-T wave moves opposite direction of QRS
- Usually full compensatory pause
what is this
PVC
what is happening?
- multiple PVC’s
- QRS is elevated ST segment is down with a notch in it, possibly a P wave
what is this?
run of PVC’s
Run >3 is considred Ventricular Tachycardia for at least 30 seconds or more
what is this?
- wide QRS
- ST segments inverted
- Multifocal premature ventricular contractions
- hemodynamically unstable
What is ventricular premature contraction with R on T phenomenon?
- The beat is hitting during the ventricular repolarization
- can lead to v tach or v fib
- watch patient closely
What is an Accelerated idioventricular rhythm?
- Good sign of reperfusion, indicates that the thrombolytic agent is working
- Do not treat just leave alone
How do you treat PVC’s?
- If stable no treatments
- If sx in setting of ACS use Metoprolol
- If unstable Amiodarone, lidocaine, Procainamide
What is V tach?
- 3+ consecutive bizarre QRS complexes
- Ventricular rate is 120-200
- Usually regular with a wide ARS
- P wave is lost and if it is seen it has no relation to QRS
- Lasts longer than 30 seconds
what is this?
- Paroxysmal Ventricular Tachycardia beating around 150-250
- Wide QRS
- ST going opposite direction
- Suddenly occurred
what is happening?
- Runs of V tach
- first QRS is inverted ST elevated
- 4 QRS elevations in a row
- end of strip is more runs of v tach
- Multifocal (from different sites, they don’t all look alike)
what is happening?
from one foci, they all look alike
V tach
what is this?
- Wide QRS 200+bpm
- Premature Ventricular contraction but sustained so it is Vtach
What is Torsades de Pointes?
- Twisting of the points
- QRS swings from positive to negative
- May be inherited from Prolonged QT
- Could be acquired by meds, electrolyte imbalances, alcohol
what is the diagnosis? what can happen later on?
This is Torsades de Pointes, this can lead to V tach
How do you treat torsades?
- MgSO4
- Overdrive pacing
- Isoproternol
- Get off what might have induced the arrhythmia
What is Ventricular fibrillation?
- Disorganized depolarization
- Not an effective pump
what is this?
v fib
what is this?
vfib
differentiate from artifact, if patient is stable and talking probably not v fib
