cariophysiology EKG rhythms... not blocks Flashcards
sinus rhythm heart rate
60-100
sinus arrhythmia: cause
ANS changes pacing upon respiration.. its normal
three types of atrial irregular rhythms
wandering pacemaker
multifocal atrial tachycardia
atrial fibrillation
wandering pacemaker characteristics - 4
irregular rhythm cagegory
- P wave shape changes
- atrial rate is less than 100
- irregular ventricular rhythm
multifocal atrial tachycardia characteristics - 4
irregular rhythm category
- p wave shape changes
- atrial rate is over 100
- irregular ventricular rhythm
atrial fibrillation characteristics - 3
irregular rhythm categorm
- continuous chaotic atrial spikes
- irregular ventricular rhythm
escape rhythm =
automaticity focus escapes overdrive suppression and PACES at its intrinsic rate
escape beat
automaticity focus TRANSIENTLY escapes overdrive suppression to emit ONE BEAT
atrial escape rhythm characteristics - 3
- normal sinus rhythm then sinus arrest
- the escape rhythm has a different P shape
- new pacing at 60-80 bpm
junctional escape rhythm characteristics - 4
- normal sinus rhythm then sinus arrest
- NO P wave, OR NEGATIVE P wave because this pacing is from AV node
- aka idiojunctional rhythm
- new pace is 40-60bpm
ventricular escape rhythm characteristics - 5
- normal sinus rhythm then sinus arrest
- regularly spaced P waves, but they don’t make QRS
- wide QRS because
- aka idioventricular rhythm
- new pace is 20-40 bpm
atrial escape beat characteristics
same as atrial escape rhythm, but it only happens for one beat because the SA node misses a cycle
AV junctional escape beat
same as juncitonal escape rhytm but it only happens for one beat
ventricular escape beat
same idea as ventricular escape beat EXCEPT….
this happens when both the SA node and the AV node are suppressed (usually by parasympathetics)
when it escapes, the QRS is HUUUUGGGEEE
premature atrial beat characteristics - 4
- premature P wave (because its irritable)
- therefore, prematue QRS
- the premature wave is from an ATRIAL focus, so the P wave looks different from normal
- premature beat resets the system so the subsequent beats line up with the premature one
what sometimes happens with a premature atrial beat
sometimes, the ventricle isn’t totally REpolarized from the last beat so its wide. we call this “aberrant ventricular conduction”. the wide QRS is ONLY for the premature beat
nonconducted premature atrial beat - 3
- the SA node paces, but the AV node decides its not ready yet, so you get NO QRS and T
- the SA node paced, so its STILL the boss
- this looks dangerous (like a block) but is not
atrial bigeminy
when a premature atrial beat keeps tagging along on the end of a normal beat
premature junctional beat
- irritable AV junction fires prematuely
- sometimes makes the P wave negative
- can get a squggly QRST if one of the bundle branches is still trying repolarize
- this is different from ventricular escape because its NOT WIDE
- this usually resets the SA node via retrograde atrial depolarization
AV (junctional) bigeminy
when one premature junctional beat keeps tagging along the end of a normal beat
what causes a juncitonal focus irritable
low oxygen
low potassium
pathology
cocaine
examples of low oxygen that causes junctional focus irritability
airway obstruction
air with poor O2
poor oxygenation in lungs (pneumothorax or embolus)
poor coronary blood supply
example of pathology that causs junctional focus irritability
mitral valve prolapse, stretch, myocarditis
what should you know about cocaine and hearts
- it can make either ATRIAL OR JUNCTIONAL foci irritable
- can cause a coronary spasm…. hypoxic heart in addition to irritable heart
- thats not really a great combo.
premature ventricular contraction
exactly what it sounds like. this has a wide QRS of opposite polarity from normal
(aka if QRS is normally going up, this one will be wide and down)
ventricular parasystole - 3
- ventricular focus has an entrace blook so it can’t be overdrive suppressed
- pacing happens from two different locations at two different rates
- distance between the vetricular complex is usually large
ventricular tachycardia
a run of three or more PVCs
if a PVC tries to on a T….
WATCH YOUR PATIENT CAREFULLY!!!
(did you like that rhyme)
this is a deadly arrhythmia
heart rate of a paroxysmal tachycardia
150-250
heart rate of flutter
250-350
heart rate of fibrillation
350-450
paroxysmal tachycardia characteristics -3
- rapid firing of irritable atrial automaticity
- P wave is different from normal
- can be triggered beause of a premature stimulus from elsewhere
PAT with (AV) block - 4
- rapid rate,
- spiked P’ wave
- 2:1 ratio of P’ to QRS
- suspect digitalis excess or toxicity
paroxysmal junctional tachycardia characteristics
- caused by irritable pacing of Av junction
- junctional focus may also cause retrograde depolarization of atrium causing weird P’ waves
weird p’ waves in paraoxysmal junctional tachycardia look like (3 types)
inverted P’ immediately before each upright QRS
inverted P’ after each upright QRS
inverted P’ buried within each QRS
supraventricular tachycardia - 3
- produces both paroxysmal atrial tachycardia and paroxysmal junctional tachycardia
- sometimes the P’ runs into the preceding T wave
- this is an umbrella term for both tachycardia types, especially if the waves are too close to distinguish the origin of the tachycardia… it doesn’t really matter anyway since the treatment is the same
paroxysmal ventricular tachycardia - 2
- irritbalbe ventricular automatciity focus that paces quickly
- to me this looks like upside-down “U” s
torsades de pointes EKG - 2
- upside-down U that gets taller and smaller and taller and smaller
- rate is 250-350 bpm
torsades de pointes cause
low potassium, potassium channel blockers or any other condition that will lengthen the QT setment
atrial flutter EKG
“saw tooth” baseline. BE ABLE TO DISTINGUISH THIS FROM A PAT WITH AV BLOCK
ventricular flutter - 2
- this looks like a sine wave…. NOT upside down U
- rate is 250-350
wolff-parkinson-white sydrome
- P wave with a delta wave up to R
- to me, its a P wave with a swoop up to the R
- its from a “bundle of Kent” that lets the depolarization travel from the atrium to the ventricle…. its not supposed to do that
