EKG Flashcards
what are the three cogs in the gas exchange diagram
muscle, heart, and lungs
what three things are most vital to PT EKG interpretation
rate, rhythm, and ischemia
what is standard resting myocardium resting membrane potential
-90 mV
describe a positive wave
depolarization from the endocardium to the epicardium
why use a 12 lead
standardized, 3D view of the heart
what is telemetry and why use it?
4 chest leads and little box on the patient’s hip useful for remote monitoring and mobilization
what is a holter monitor
long term EKG that can be employed if a patient feels their own dysrhythmia
Describe limb leads
4 electrodes producing 6 views of the heart
I, II, III and aVR, aVL, and aVF
describe chest leads
6 electrodes for 6 views of the heart
V1-6
what is the normal conduction pathway (8 steps)
- SA node (pacemaker)
- intranodal branches and Bachman’s Bundle
- Atrium
- AV node
- Bundle of His
- R and L Bundle Branches
- Purkinje fibers
- Ventricles
what allows the electrical wave of depolarization to go from the pacemaker cells through the myocardium?
gap junctions
If the R arm is the “cold” lead and the L arm is the “hot” lead…
- which way will the EKG deflect during a depolarization to the L arm
- which way will the EKG deflect during a depolarization to the R arm
- which way will the EKG deflect during a repolarization to the R arm
- positive to positive = upward deflection
- positive to negative = downward deflection
- negative to negative = upward deflection
what is going on here
atrial depolarization
what is going on here
AV node delay - charge returns to isoelectric line b/c no electrical activity currently
what is going on here
septal depolarization: L bundle branch moves faster than R bundle branch
what is going on here
ventricular depolarization
what is going on here
the downspike begins as the vetricles complete their depolarization and the EKG returns to the isoelectric line
what is going on here
the ventricles have completed depolarization and the EKG has returned to the isoelectric line - no electrical activity of the heart
what is going on here
ventricular repolarization
where is atrial repolarization on an EKG
trick question, it’s masked by the QRS complex
what will an EKG look like if the “hot” lead is on the right? (as in aVR?)
everything will be the same, but inverted
what is happening in NSR
- HR = 60-100
- SA Node is in control
- rhythm is regular
what is a normal PR interval? how does 1st degree AV block differ?
< 0.2s or 1 large box; prolonged or delayed p wave
what does this EKG indicate?
ST segment depression of 1mm = myocardial ischemia
the greater the ischemia, the greater the depression
what does this EKG indicate?
STEMI - acute myocardial infarction
how much time elapses between these marks?
3 seconds
what is the heart rate?
80 bpm
what is the heart rate using the rule of 300s?
75 bpm
when can you use the rule of 300s
only on rhymical EKGs
the rule of 300s can also be used on an EKG ruler, but what is primary difference when using the EKG ruler
you need to look 3 cycles from the reference arrow
what qualifies as bradycardia and tachycardia? in what populations do you see these rhythms as “normal”
- bradycardia - <60 bpm - normal in athletes
- tachycardia - >100 bpm - normal in babies
what is the HR? name the EKG
40 bpm - sinus bradycardia
what is the HR? name the EKG
140 - sinus tachycardia
what is the HR? name this rhythm
120 bpm - sinus tachycardia
what’s the inherent rate of…
- the SA node
- atria
- AV node
- ventricles
- 100 bpm
- 75 bpm
- 60 bpm
- 30-40 bpm
with dysrhythmia, how would you measure the heart rate MOST reliably
very important
auscultation
name this rhythm abnormality
L atrium PAC
(LA b/c T wave is inverted)
name this rhythm abnormality
RA PAC
what is this rhythm abnormality and how can you tell
PNC aka early AV node contraction
“no P wave with a normal QRST”
what is this rhythm abnormality and how can you tell
PVC b/c wide, wild, and bizzarre
what is a compensatory pause?
a pause after a premature contraction in order to correct for the inadequate filling. The pulse after the premature contraction will feel weaker, but the second pulse will feel stronger
how many premature contractions per minute do we contact the doctor?
6 per minute
what is the difference between unifocal and bifocal/multifocal PVCs?
unifocal PVCs all look the same, bifocal two look the same, multifocal - PVCs look different - mutlifocal PVCs are usually worse
what is the HR and how would you name it?
50 bpm
normal sinus bradycardia with 2 unifocal PVCs
what do you call this and would you exercise this patient?
bigeminy
what is this rhythm
trigeminy (2 normal and 1 abnormal)
what is this rhythm?
quadrigeminy (3 normal and 1 abnormal)
what’s the HR and what would you name this
80 bpm
quadrigeminy PVC
name this
couplet
what do you call this and why
v-tach because more than 3 PVCs in a row
T/F: all patients who are in v-tach feel it
false, some patients can be unaware that they are in v tach
what is this? where is the ectopic site?
paroxysmal atrial tachycardia (PAT) - the ectopic site is in the RA because of the upward P wave
what is the difference between PAT and Normal Sinus Tach
PAT jumps up to a higher heart rate immediately whereas normal sinus tach gradually builds up
what is this and how can you tell
supraventricular tachycardia (SVT) - cant distinguish p vs t waves but the QRS is normal
what is the HR for people in vtach?
150-250 bpm with >3 PVCs in a row
what is this?
v tach
what is this
atrial flutter - multiple p waves for every qrst
what is this
A-fib - wiggly line with irregularly spaced spikes
what is the HR? How would you name it? where is the ectopic site?
90 bpm
A-Fib with PVC couplet
ectopic sites all over the atrium and one in the ventricle
what is this and what is the usual HR for these patients? what would you do?
ventricular flutter - 250-350 bpm
most of the time these patients are unconscious and you wont feel a pulse
what is this
V Flutter
what is this? what would you do?
V-Fib
activate EAP and begin compressions
what is this?
V Fib
name this rhythm
quadrigeminy STEMI with PVC landing on t wave
what are the three escape beats
atrial, nodal, and ventricular
name this
Atrial Escape Beat
name this… why?
nodal escape beat - b/c no p wave and QRST looks normal
name this and why
ventricular escape beat - flat line followed by PVC
how do you determine a 1st degree AV block?
PR interval greater than one large block (> 0.2s )
name this
1st degree AV block with ST depression
what is this, how can you tell
second degree heart block
multiple (2-3) P waves to cause a QRS
what is this and how can you tell
3rd degree AV block b/c p waves dont match QRS
where does an NSTEMI occur? STEMI?
NSTEMI = sub-endocardial
STEMI = transmural
