Bundle Branch Blocks Flashcards
if the t wave is opposite the direction of the last QRS wave this is called
discordance; normal
if the t wave is the same direction as the last wave in the QRS complex then this is
concordance; abnormal
what can the axis of a RBBB be
normal, right, even left
what is the criteria for a RBBB
QRS > 0.12 seconds
RsR’ complex in V1 and V2: rabbit ears
deep slurring of the S wave in I and V6
what does a QR’ wave signify
found in RBBB; signifies an old anteroseptal MI (ASMI)
-Q waves in lead V1 and RBBB
what does a QR’ wave look like
in lead V1 its a q wave down and a positive R’ wave
name some causes of RBBB
ASDs cardiomyopathy myocarditis CHF Duchenne's MD Brugada
what is a PE finding associated with RBBB
a widely split S2
what is the criteria for a LBBB
QRS > 0.12 seconds
broad QS or rS in V1
monophasic R wave in lead I and V6
t wave should be opposite final QRS wave= discordance
what are the possible causes of LBBB
HTN CAD CHF HOCM Aortic stenosis lyme dz myocarditis
T/F: it is easy to diagnose infarct in the presence of LBBB
false; very difficult!
when do you worry about LBBB
ALWAYS: its CAD until proven otherwise
what is IVCD
intraventricular conduction delay
What is the criteria for IVCD
mixed appearance of RBBB and LBBB
QRS > 0.12 seconds
V1 looks like LBBB
leads I and V 6 look like RBBB
when you find IVCD what should you think is the cause immediately
hyperkalemia
