normal ecg and arrythmias Flashcards
3 lead placement
5 lead placement
12 lead placement
cardiac conduction
SA node to AV node to bundle of his to left and right bundle branches to perkinjie fibers
A normal P wave
small round and less than 3mm tall
no more than .1 sec
wave caused by SA node (atrial systole)
Q wave
produced by initial depolarization in IVS
1mm deep and 1mm wide
R wave
remaining of ventricular depolarization
ventricular systole
S wave
ventricular depolarization
QRS complex
between .06 and .09 seconds
bundle of his , left and right bundle branches and the purkinjie fibers cause the QTS complex
T wave
ventricular repolarization
IVRT time
less than 6mm with a duration of .01 to .25 sec
diastolic portion of the heart
normal RR interval
one minute is one heart rate
peak to peak
PP interval
in normal the PP and RR intervals are equal
PR interval
measures atrioventricular activation time
QRS interval
time from the beginning of Q to the end of the S wave
QT interval
ventricular systole
ST segment
ventricular ejection is occuring
absolute refractory period
second heart contraction cannot occur
relative refractory period
a strong enough stimulus can cause a second heart contraction
bradycardia
less then 60 BPM
tachycardia
more than 100 BPM
normal sinus rhythm
ekg of bradycardia
ekg of tachycardia
arrhythmia
the heart beats with irregular or abnormal rhythm
types of arrhythmia
PVC:premature ventricular contraction bigeminy trigeminy atriventricular block right/left bundle branch block AFIB atrial flutter
what is a PVC
where the purkinjie fibers initiate the contraction of the ventricles
may be felt as a palpatations, the ventricles contract before they are filled with blood
loss of an A
what is a Bigeminy
where a short and long HB alternate
usually due to an ectopic heart beat like a PVC
what is a trigeminy
2 sinus beats with an ectopic heartbeat
AV (atrioventricular) block occurs when?
there is an impairment of conduction between the atria and ventricules
causes of an AV block
MI, cardiomyopathy, congenital heart disease, valvular disease
first degree AV block
PR interval great than .20 sec
E and A waves merge because of premature closer of MV
second degree AV block type 1
the PR interval gets longer and longer with each beat until QRS is dropped
second AV block type 2
PR intervals are constant and long prior to the QRS being dropped
third degree AV block
no association between P waves and QRS
right bundle branch block (RBBB)
the RV is not activated by impulses
conduction through myocardium is slower than the purkinjie fibers and the QRS becomes wider
seen in leads V1 and V2
left bundle branch block (LBBB)
activation of LV is delayed which causes the LV to contract later than the RV
on echo there is paradoxical septal motion
ventricular tachycardia
EKG will show at least three wide QRS complex and may result in Vfib
supraventricular tachycardia
BPM 150-220
fast rhythms arising from upper part of heart atria or AV node
4 types of SVT
AFIB
atrial flutter
paroxysmal SVT
wolfparkinson white syndrome
svt ekg
AFIB
most common
chronic AFIB can lead to risk of death
causes of AFIB
the SA node in the RA are overwhelmed by disorganized electrical impulses.
MS (most common reason) , and high blood pressure increase risk of AFIB
AFIB symptoms
usually no symptoms
but there may be palpitations, fainting, chest pain or CHF
treatment for AFIB
synchronized electrical cardioversion
surgical catheter based ablation
anti clotting medication
medication for rate control
In what leads is an RBBB seen
V1 and v2
On echo what is seen which a LBBB
ivs paradoxal motion
What leads is an LBBB seen
V5 and 6
4 main types of SVT
A fib
Atrial flutter
Paroxysmal svt
Wolf parkison white syndrome
