EKG Flashcards
phase 0 of the cardiac action potential cycle
depolarization and rapid entry of NA
phase 1 of the cardiac action potential cycle
early depolarization due to the entry of K
phase 2 of the cardiac action potential cycle
plateau continues with slower entry of Ca
phase 3 of the cardiac action potential cycle
repolarization: K+ moves out of the cell
phase 4 of the cardiac action potential cycle
resting
what is a normal P-R interval
0.12 - 0.20 secs (3-5 small boxes)
what is normal QRS interval
0.06-0.10 secs (1.5-3 small boxes)
Assessment of the cardiac cycle
1) P wave: before QRS and Upright
2) P-R interval: 0.12-0.20 seconds (3-5)
3) QRS interval: symmetrical?
4) QRS time: 0.06-0.01 secs? (1.5-3)
5) T wave: is it there? upright and normal
6) R-R is it regular
7) HR is it regular
8) pt S/S
Causes of PAC premature atrial contraction
- idiopathic
- sign of CVD
- HTN
- pregnancy
- COPD
- hyperthyroid disease
- stress or extreme fatigue
what to do if you see a PAC
continue with treatment. document. decrease activity if it continues to occur.
causes of atrial tachycardia (SVT)
- HTN or cardiomyopathy
- previous MI
- Alcohol or stimulus drugs
- irritable focus
- idiopathic
what to do if you see atrial tachycardia (SVT)
decrease intensity, monitor vitals
Atrial fibrillation (A-fib)
electric signals traveling too fast that it makes the atria quiver and not be able to squeeze strongly. Irregular rhythm and decrease in atrial kick
Atrial Flutter
sawtooth like regular rhythm
electrical impulses travel in a circle instead of a straight line
causes of A-fib and A-flutter
- age or genetics
- Heart disease or underlying heart disease
- increased alcohol consumption
- endocrine, neurologic or hemodynamic disorders
- sleep apnea
- inflammation
symptoms of A-fib and A-flutter
- tachycardia
- SOB
- dizziness
- decrease ex tolerance
- chest pain
- night sweats or palpitations.
what to do if a pt is A-fib or A-flutter
If new onset: STOP call team and monitor pt
premature ventricular complex (PVCs)
- the sinus node is not reset and continues to depolarize on time through PVCs
- Can be uni or multifolcaled
- Runs of threes leave them be
- characterized by a long and widened QRS interval
Causes of PVCs
- caffeine intake
- electrolyte imbalances
- hyperthyroidism
- cardiac problems
- anemia
- idiopathic
symptoms of PVCs
- often asymptomatic or benign palpitation
- lightheadheadness, chest pain, or discomfort, dyspnea and anxiety
- rarely syncope
Ventricular Tachycardia (V-tach)
bizarre widened QRS complexed, no P waves and HR over 100 with regular rhythm
Causes Ventricular Tachycardia (V-tach)
- increase ventricular rate leads to a low CO and low systemic hypofusion
- life threatening if sustained more then 30 secs.
- ischemia or MI scaring, acute coronary syndrome
symptoms of V-tach
- syncope
- SOB
- Cardiac arrest or sudden cardiac death
what to do in a V tach
STOP call rapid responce team or code
Ventricular fibrillation (v-fib)
loss of electrical organization leading to irregular firing- widened QRS interval
causes of ventricular fibrillation (V-fib)
- MI
- electrolyte imbalances, especially hypokalemia
symptoms of v-fib
- syncope or near syncope
- SOB
- cardiac arrest
poem for a heart block
If R is far from P you have a first degree, Longer, longer, longer you have a winkebach, if some of the Ps don’t get through you have a Mobitz 2. If ps and Qs don’t agree you have a 3rd degree
1st degree AV block
widened P-R interval
consistant rhythm
2nd degree AV block type 1 - Winklbach
P-R interval constantly getting wider then a drop of the QRS interval - constantly off
2nd degree AV block type 2
P-R intervals constantly wide with a drop on the QRS interval - random and not constant
3rd degree AV block
widened P-R interval and widened QRS with random QRS drops.
causes of AV block
- CAD
- cardiomyopathy
- autoimmune disorders
- inflections, cancers, inflammation
- congenital
- hyperkalemia
