Intraventricular conduction defects Flashcards
in ___BBB the ST-T is opposite the direction of the QRS
RBBB
the atrioventricular pathway is through the Bundle of Kent
Wolff Parkinson White (WPW)……….. FYI: only a portion goes through the Bundle of Kent, the rest goes through the AV node
if you see a LAD, you should infer
LAHB (left anterior hemiblock)
wide QRS + wide/ notched/flattened R (in lead 1 and V6)
LBBB (this is the M in WiLliaM)
how do you determine LVH in the limb leads
R (in lead 1) + S (in lead 3) > 25
pre excitation syndrome with a normal QRS
LGL
LBBB
QRS > 0.12 sec, deep/ wide S in V1/V2, wide R in leads 1 and V6, R waves may be prolonged/ notched/ flattened (WiLliaM in V1 and V6)
RBBB + LPHB
bifascicular block
M shape in V1
RBBB
if EKG looks like BBB, but the QRS is normal, it can be referred to as
incomplete BBB pattern AND either hypertrophy OR cannot r/o hypertrophy
tall R in lead 3, deep S in lead 1, normal QRS, strong RAD
LPHB
tall R in lead 1, deep S in lead 3, normal QRS, strong LAD
LAHB
RBBB
QRS > 0.12 sec, M shaped RR’ in V1, wide/slurred S in V6 (MaRroW in V1 and V6)
patients with WPW are vulnerable to
PSVT
how do you determine LVH in the augmented leads
R (in aVL) > 11
how can you determine a BBB
QRS greater than 0.12 sec and RR’ configuration in chest leads
pre excitation syndrome with a wide QRS
WPW
RBBB + LAHB
bifascicular block
where are you looking for atrial enlargement
lead 2 and V1
LPHB goes with
RAD
how do you determine LVH in the precordial leads
S (in V1 or V2) + R (in V5 or V6) > 35
how can you determine a hemiblock
a change in the QRS axis but the QRS duration is NOT prolonged
causes of nonspecific IVCD
ventricular hypertrophy, MI (peri-infarction blocks), antiarrhythmics (quinidine, flecainide), hyperkalemia, paced complexes
if EKG looks like BBB, but the QRS is normal, think
hypertrophy
