Right Atrial Enlargement: Lead II
tall peaked P wave (>2.5mm)
RAE: V1
biphasic P wave
LAE Lead II
wide notched prolonged P wave (.12s)
LAE V1
biphasic P wave with negative side larger than positive
RVH V1 & V2
tall R waves
RVH V5 & V6
deep S waves
RVH Lead I
negative QRS
RVH V1
Positive QRS
RVH all leads
ST depression, T wave inversion
RVH mean axis
right axis deviation
LVH equation
S wave in V1/V2 + R wave in V5/V6 >35mm
LVH all leads
St depression and T wave inversion
LVH V1-V6
R wave amplitude greater or equal to 25mm
LVH aVL
R wave more than or equal to 11-13mm
1st degree AV block
Long PR segment with QRS following (>.2s)
2nd degree AV block Type I
Pr intervals progressively increase until QRS is dropped
2nd degree AV block Type II
PR intervals are constant with dropped QRS
3rd degree AV block
complete dissociation between P waves and QRS complexes, unchanged PR intervals
RBBB V1
wide positive QRS, rabbit ears
RBBB Lead I
S wave present (shouldn't be wider than half a box)
LBBB V1/V2
wide notched negative QRS (in most leads)
LBBB all leads
ST-T changes opposite of the R waves proceeding them
LBBB V5/V6
tall notched positive R waves
LBBB I, aVL, V5, V6
absence of small normal Q waves
LBBB mean axis
possible left axis deviation
STEMI ST elevation
aVL, I, V2, V4, V6
STEMI ST depression
II, III, aVF *reciprocal findings
STEMI Q waves
pathologic findings: 1/3 height of QRS, .4s long
NSTEMI all leads
ST depression
NSTEMI reciprocal findings
NONE.
Artifact
NOT A PATIENT CONDITION
Artifact causes
patient movement,poor skin prep, old electrodes
Low voltage limb leads
QRS <5mm in all
Low voltage precordial lead
none with a total voltage of >15mm
Low voltage ecg calibration
must be properly calibrated to have this finding
Types of ST segment change
ST depression and ST elevation
ST depression due to oxygen demands
heart rate, wall stress, contractility
ST depression due to oxygen supply
blood flow
ST depression due to exercise ischemia
heart vessels are partially occluded which is made obvious by exercise, higher need for blood causes less blood to get through
T wave inversion reasons
coronary heart disease, angina pectoris
Digitalis effect
messes with baseline ST segments, cannot read for ischemia, causes sloping ST segment
Prinzmetal Angina
ST elevation
Ventricular Aneurysm
ST elevation, T wave inversion
Pericarditis all leads except aVR
ST elevation
Pericarditis all leads
PR segments are depressed
Early repolarization
ST elevation in normal hearts
Juvenile Pattern V1-V4
T wave inversion
Hypocalcemia
QT interval prolongation (>.44)
Hypercalcemia
QT interval shortened
Hypokalemia
prominent U wave (only visible during bradycardia)
Hyperkalemia
Tall, tented, peaked T wave, moves toward ventricular fibrillation
Normal Sinus Rhythm
Rhythm: regular Rate: 60-100bpm P waves (in LII): max .12s PR interval: .12-.2s QRS: less than .1
Sinus Arrhythmias
Rhythm: irregular & sinus Rate: any rate P waves, PR interval, QRS normal
Sinus Arrhythmias Breathing
Decreases on expiration, increases on inspiration
Sinus tachycardia
Rhythm: regular Rate: higher than 100bpm P waves: normal PR interval: normal QRS: normal
Sinus bradycardia
Rhythm: regular Rate: less than 60 bpm P wave, PR interval, QRS: normal
Sinus Exit Block
Dropped beat, beat comes back in line with rhythm from before
Sinus exit block PR intervals
PR intervals are normal and regular
Sinus Arrest
Dropped beat, rhythma before and after the pause do not line up
Premature Atrial Contraction (PAC)
Premature beat, narrow QRS complex
Blocked PAC
Look at T wave prior (big/different than others in same lead) & beat after
Blocked PAC physiology
PAC happens so quickly that heart cells are in absolute refractory period, unable to conduct impulse
Premature Junctional Contractions Three P wave options
Absent, inverted, retrograde
PJC: Absent P wave
atria and ventricles depolarize at same time
PJC: Inverted P wave
in correct sport, upside down, beat started at AV junction
PJC: Retrograde P wave
Ventricles depolarize between atria
Accelerated Junctional Rhythm: multiple leads
inverted P wave, P wave after QRS OR no P wave
Accelerated Junctional Rhythm: BPM
60-100 bpm
Atrial Tachycardia: all leads
three or more PAC that occur consecutively
Atrial Tachycardia: BPM
200 +/- 50 bpm
ST elevation
aneurysm, evolving MI, pericarditis, Prinzmetal angina, early repolarization
ST depression
ischemia, reciprocal change of MI, NSTEMI, R/L BBB, Digitalis, R/L VH
Left Anterior Hemiblock Lead I
small Q wave
Left Anterior Hemiblock Lead III
small R
Left Anterior Hemiblock QRS
QRS normal or widened to .1s
Left Anterior Hemiblock mean electrical axis
Left shift of electrical axis: -45 to -90
Left Posterior Hemiblock Lead I
small R wave
Left Posterior Hemiblock Lead III
Small Q wave
Left Posterior Hemiblock QRS
normal or widened to .1s
Left Posterior Hemiblock electrical axis
Rightward shift of electrical axis: 120 to 180