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
what is the clinical significance of LAH
most commonly seen in Acute anterior MI
acute inferior awl MI
in children: tricuspid atresia, AVSD
myocarditis
how do you diagnose LPHB
diagnosis of exclusion
RAD; not extreme
deep S in lead I
qR in leads II, III and AVF
what is the significance of LPHB
rare in children
inferior MI
ateriosclerotic valve dz
what is a bifasicular block
combo of RBBB + LAH/ LPH
which combo of bifasicular block is most alarming and can lead to complete heart block
RBBB+ LPH
what is a trifasicular block
prolongation of the PR interval= first degree AV block
-RBBB
-LAH or LPH
BAAADD NEWS BEARS= leads to complete heart block
