EKG Abnormalities Flashcards
what abnormality is seen in V1 with RBBB?
called the rSR’ where the r is the first spike from IV septum depol then S is lower cause of the movement to left ventricular then R’ is from the spike of the right ventricle finally contracting
how long does the QRS need to be to have a RBBB of LBBB?
greater than 0.12 or more than 3 small boxes
what happens to the T wave in the leads with rSR’ pattern when having RBBB?
will have an inverted T wave
name the four EKG abnormalities found with a RBBB?
prolonged QRS greater than 0.12
rSR’ pattern in V1 lead
long S wave in lead 1 and V6
T wave inversions in V1-2
what happens in lead I and V6 in RBBB?
they get a widened S wave
what four leads to note with RBBB?
lead 1
V1, V6
maybe V2
four potential cause of RBBB
pulmonary hypertension
atrial septal defect
pulmonary embolism
CAD
four criteria for a LBBB
prolonged QRS of more than 0.12 seconds rS or QS wave in V1 broad/notched R wave in lead I or V6 no Q waves in I or V6 T wave opposite RS deflection
what should you find in V1 with a LBBB?
rS or QS wave
what should you find in lead I or V6 in LBBB?
broad/notched R wave and absence of Q waves
what happens to T waves in LBBB?
they are opposite of direction of QRS deflection
what three leads to look at for an LBBB?
lead I, V6, and V1
four possible causes of LBBB?
hypertensive heart disease
valvular disorders
CAD
cardiomyopathy
what does ventricular pacing look like on EKG?
looks like a bundle branch block with little snips right before the QS complex
WPW EKG abnormality and why?
has a delta wave that leads up the R wave…this is because the ventricle has been pre excited by the bundle of Kent
bundle of Kent
bypass tract to LV in WPW
What do Sodium channel blockers do to the QRS?
they make it wider
name a class of sodium channel blocker
Class I anti arrythmics
5 cause of low voltage QRS
hypthyroidism, amyloidosis, pleural/pericardial effusion, end stage myocardial disease, obesity, pneumothorax
hyperkalemia
high potassium
hyperkalemia effect on QT interval
shortens
hyperkalemia effect on T wave
increases…looks like spike
what is hyperkalemia prone to?
ventricular tachycardia or fibrillation
what is the new wave we get with hypokalemia and when does it appear?
the new U wave comes right after the T wave
what happens to the T wave in hypokalemia?
T wave will be slower and dampened…can be inverted
what happens to the QT interval in hypokalemia?
gets longer…too long
name the three changes of hypokalemia in EKG
the QT interval lengthens…the T wave gets smaller and can invert…U waves appear
name the two changes with hyperkalemia of the EKG
T waves are higher and spikey
QT is shorter
what two changes do we see with hypercalcemia in EKG?
osborn waves..waves directly following the R wave
and shortened ST segments
Two changes to EKG due to hypocalcemia?
long ST segment…leading to long QT interval
how to calculate the QTc
take length of QT in seconds and divide by square root of the RR interval
when do we worry about the length of the QT interval
if it is longer than 1/2 RR
3 congenital channelopathies leading to lengthened QTs
loss of function Ks channel
loss of function Kr channel
gain of function Na channel
what is a disease risk with prolonged QT?
Torsade de pointes
