ECG part 2 (incomplete, important info) Flashcards
PR interval short vs long shows what
less 3 boxes: preexcitation syndrome
more 5 boxes: AV node block (some block)
long QT main danger
predisposes to torsades de pointe
main causes of short QT
hypercalcemia
tachycardia
main causes of long QT
*antiarrhythmic drugs
hypocalcemia
hypokalemia
MI
left axis deviation noticed how
negative QRS on lead 2
right axis deviation noticed how
negative QRS on lead 1
what left axis deviation can show
MI
left anterior fascicular block
LV hypertrophy
what right axis deviation can show
RV hypertrophy
acute right heart strain (massive PE)
left posterior fascicular block
2 P wave abnormalities
LA enlargement or RA enlargement
how see RA enlargement
lead II: higher first bump on P
how see LA enlargement
lead II: higher second bump on P
V1: amplitude of P wave 2nd bump greater than 1st bump
P waves best seen where
II and V1
3 abnormalities of QRS
ventricular hypertrophy, bundle branch blocks, pathologic Q waves in MI
how to see RV hypertrophy
Right axis deviation (lead I)
R greater than S in V1
how to see LV hypertrophy (simple)
Left axis deviation (lead II)
how to see LV hypertrophy (complicated criteria)
R in lead I 15 mm+
R in aVL 15 mm+
S in V1 + R in V5 or V6 35mm+
how to see bundle branch block in general
QRS 2.5-3 boxes: incomplete block
QRS 3+ boxes: complete block
how to see right bundle branch block
bunny ears in V1 and V3
how to see left bundle branch block
bunny ears in lead I, aVL, V5 and V6
pathologic Q wave description
width 1 box +
depth 25% of QRS or more
4 localizations of MI
anteroseptal
anterolateral
anteroapical
inferior
anteroseptal MI: path Q waves where
V1 and V2
anterolateral MI: path Q waves where
lead 1, aVL, V5, V6
anteroapical MI: path Q waves where
V3 and V4
Inferior MI: path Q waves where
lead II, lead III, aVF
how to see transient MI on ECG
ST depression
T wave inversion
how to see acute MI on ECG
T wave elevation and permanent Q waves show old MI
how to see acute non ST segment elevation MI on ECG
ST depression or T wave inversion (these don’t go away)
TF: all ST T segments pathologies caused by MI
false, other causes like pericarditis
pericarditis findings on ECG
ST elevations on most leads (not only ones affected by infarct as in MI)
