ECG Flashcards
Limb lead reversal
negative p-wave, qrs and twave in lead 1
Low voltage
def
<5mm Limb leads
<10mm in ALL precordial leads
Hypocalcemia
prolonged QT
because of lengthened flat ST segment without change in duration or morphology of T wave
Prolonged QT
> 1/2 RR interval
not reliable with tachycardia (>100bpm)
Aflutter with pause
can see aflutter which spontaneously breaks -> sinus pause and suddenly a junctiona escape beat followed by sinus node recover (ie sinus bradycardia etc) - sinus node dysfunction has prolonged sinus node recovery time
Digitalis toxicity
Regularized afib
aflutter with 3rd deg AVB and junctional tachycardia
prominent U-waves
Junctional rhythm
40-60bpm
Jnc Tach
> 60bpm
more likely to occur with inferior MI
Normally conducted beat after paced beat
can have twave inversion and not sensitive for ischemia so do not code ischemia changes
Failure to sense
look for premature v-pace beat (
T wave memory
T wave changes looking like ischemia persist for several days after patietn returns to normal AV conduction and v activation after prolonged 100% pacing time (or after WPW with pathway ablation now conducting through normal AV conduction system
RVH with pulm HTN/PE
Tall R wave V1
Acute PE
S wave in I (RAD from LPFB)
Q wave III
inverted T in III
Accessory pathway localization
Step 1: QRS Transition
-R/S transition before V1 (Tall R wave V1)/RBBB pattern = left sided pathway
-later than V2 (>V2) S wave in V1, LBBB = right sided pathway
-Transition V1-V2=septal
Step 2: Delta wave polarity
-positive in 2/3 leads = anterior
-negative in 2/3 lead= posterior/inferior
Brugada pattern
h/o syncope
Type I pattern (dx of brugada): J-point elevation >2mm with COVED donwloping ST segments
Type 2: J-point nelevation >2mm and saddleback shaped ST segment elevation >1mm
SCN5A
a/w threating VT arrythmias and SCD
Resemble RBBB but lacks QRS morphology c/w RBBB in other leads ie wide slurred S waves in I and V6
Electrical alternans in patient with cancer
code electrical alternans
pericardial effusion,
SR
LPFB
RAD
small r wave in I, aVL
small q in lead III
RBBB
QRS>120ms
rsR’ complex V1
wide slurred S waves I, V6
RBBB
QRS>120ms
rsR’ complex V1
wide slurred S waves I, V6
T wave inversion opposite to terminal deflection of QRS in V1, V2 - not case with V3-6 - suggests ischemia
does not interfere with ECG dx LVH or Q wave MI
LBBB
QRS >120ms
V1 - rS (tiny R, big S - wide) with ST elev and discordant twave ie upright while S is down)
or deep QS (no r)
R waves in lateral leads (I, V5,6) M shaped, notched, monophasic or RS)
Dextrocardia vs limb lead reversal
Limb lead reversal - normal R-wave progression
Dextrocardia - REVERSE R wave pgoression (starts out big)
DO NOT CODE AXIS
Dextrocardia vs limb lead reversal
Limb lead reversal - normal R-wave progression
DO NOT CODE AXIS - technical error with lead placement
Dextrocardia - REVERSE R wave pgoression (starts out big gets smaller)
DO CODE RAD…neg qrs I, postiive in aVF
R&L Arm lead reversal
transposition of leads II, III
Transposition of leads avR and avL
Precordial lead reversal
Unexplained decrease in R wave voltage in 2 consecutuive leads (ie V1, V2) with return to normal progression in following leads (V3-6)