EKG's

Question 1

Determining axis

Answer 1

normal: up in Lead I and aVF
Left axis deviation: up in lead I and down in aVF
Right axis deviation: down in lead I and up in lead aVF

Question 2

2 causes of widened QRS

Answer 2

left bundle branch block (LBBB)

right bundle branch block

Question 3

natural progression of ischemia on ECG

Answer 3

T-wave inversion, then ST-segment changes, then Q waves

Question 4

other sign of ischemia on ECG

Answer 4

poor R-wave progression

Question 5

P mitrale means

Answer 5

LA abnormality

Question 6

P pumonale means

Answer 6

RA abnormality

Question 7

causes of narrow complex tachycardia

Answer 7

***AF with RVR
aflutter
multifocal atrial tachycardia

Question 8

first step with narrow complex tachycardia

Answer 8

look at RR interval to determine regularity (see algorithm in notes)

Question 9

left axis deviation causes

Answer 9

LVH

inferior MI

Question 10

APC on ECG

Answer 10

abnormal p wave, normal QRS (it’s a spontaneously depolarizing cell)

Question 11

PVC features

Answer 11

1) Broad QRS complex (≥ 120 ms) with abnormal morphology.
2) Premature — i.e. occurs earlier than would be expected for the next sinus impulse.
3) Usually followed by a full compensatory pause.
Discordant ST segment and T wave changes.

Question 12

T-wave inversions

Answer 12

ischemia
LVH
normal in aVR

Question 13

AV dissociation

Answer 13

no relationship between p waves and QRS complexes

Question 14

narrow complex tachycardia differential

Answer 14

irregular (Afib, Aflutter with variable block, Multi-focal atrial tachycardia)
regular (AVNRT, AVRT, sinus tachycardia, a flutter)

Question 15

AVNRT on EKG

Answer 15

• retrograde p waves (pseudo R’ waves)

- p waves may be buried in QRS complex

Question 16

sick sinus syndrome on EKG

Answer 16

runs of tachycardia interspersed with long sinus pauses (tachycardia-bradycardia)

Question 17

P pulmonale

Answer 17

peaked P waves

Question 18

rule for prolonged QT interval

Answer 18

QT greater than half the RR interval

Question 19

tombstone morphology suggests

Answer 19

anterolateral STEMI

Question 20

Right bundle branch block

Answer 20

rSR in V1

Question 21

Left bundle branch block

Answer 21

W pattern to QRS complex in V1

+ bunny ears or M pattern to QRS complex in V6

Question 22

multifocal atrial tachycardia

Answer 22

irregularly irregular narrow-complex tachycardia + at least 3 different P wave morphologies

Question 23

narrow complex tachycardia defined as

Answer 23

shorter than 3 small squares

Question 24

If bradycardic look for…

Answer 24

AV block

Question 25

Posterior MI suggested by

Answer 25

ST depression in V1-V3

Question 26

wide complex tachycardia then…

Answer 26

Vtach or SVT with aberrancy

Question 27

wide complex regular rhythm

Answer 27

VT

SVT with aberrancy (preexisting BBB or WPW)

Question 28

wide complex, irregular

Answer 28

Polymorphic V tach
AFIB w/ BBB or pre-excitation
VFib

Question 29

broad complex defined as

Answer 29

Greater than 3 boxes wide

Question 30

narrow complex, regular

Answer 30

sinus tach
Aflutter 
AVNRT 
Orthodromic AVRT
Atrial tachycardia

Question 31

narrow complex, irregular

Answer 31

AFib
MAT
AFlutter with variable conduction

Question 32

atrial tach findings

Answer 32

short PR

Question 33

LVH criteria

Answer 33

Sokolov-lyon:

S wave depth in V1 + tallest R wave height in V5-V6 > 35 mm

Question 34

RVH criteria

Answer 34

RAD + Dominant R wave in V1 (> 7mm tall or R/S ratio > 1) + Dominant S wave in V5 or V6 (> 7mm deep or R/S ratio < 1)

Question 35

RV infarction on EKG

Answer 35

ST elevation in V1 – the only standard ECG lead that looks directly at the right ventricle.
ST elevation in lead III > lead II – because lead III is more “rightward facing” than lead II and hence more sensitive to the injury current produced by the right ventricle.

Question 36

what classifies as left axis deviation

Answer 36

-30 degrees or more negative, so need significant negative in AVF

Question 37

common reason for noncompliance with antipsychotics

Answer 37

impotence + inhibition of ejaculation

Question 38

factors that increase likelihood of VT vs. SVT with aberrancy

Answer 38

Age > 35 (positive predictive value of 85%)
Structural heart disease
Ischaemic heart disease
Previous MI
Congestive heart failure
Cardiomyopathy
Family history of sudden cardiac death (suggesting conditions such as HOCM, congenital long QT syndrome, Brugada syndrome or arrhythmogenic right ventricular dysplasia that are associated with episodes of VT)