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
when I say hypokalemia, you think
U waves
QRS greater than 0.12 sec
BBB
why is the QRS wide in WPW
premature activation
the delta wave occurs b/c
a small area of myocytes are depolarized separately from the rest of the ventricles
if you see RAD, you should infer
LPHB (left posterior hemiblock) aka LPFB
RR’ in chest leads (rabbit ears)
BBB with the delayed ventricle representing R’
wide QRS + broad deep S waves (in V1-3)
LBBB (this is the W in WiLliaM)
the atrioventricular pathway is through the James fibers
Long Ganong Levine syndrome
short PR interval (less than 0.12)
pre-excitation syndromes (accessory conduction pathways that exist between atria and ventricles)
tall R in lead 1, deep (neg) S in lead 3, normal QRS
LAHB (plus you’ll prob see LAD)
where are you looking for BBB
V1 and V6
a slurring in the initial portion of the QRS with a wide QRS and short PR interval
delta wave seen in WPW
prolonged QRS without features of RBBB or LBBB
nonspecific IVCD (intraventricular conduction delay)
deep (neg) S in lead 1, tall R in lead 3, normal QRS
LPHB (plus you’ll prob see RAD)
wide QRS + wide S (in lead 1 or V6)
RBBB
how do you determine RVH
RAD or R>S (in V1) or S>R (in V6)
LAHB goes with
LAD
wide QRS + RR’ in V1
RBBB
a change in the QRS axis but the QRS duration is NOT prolonged
hemiblock
