ECG Signs Flashcards
1st Degree Heart Block
PR Interval is > 200ms/5 small squares
P wave may become lost in proceeding T wave
Right Bundle Branch Block
Broad QRS complexes
Positive V1
May have inverted T waves in V1-V3
Left Bundle Branch Block
Broad QRS complexes
QRS complex downwardly deflected in V1
May have inverted T waves in V4-V6
Right Axis Deviation
Lead III is most positive
Lead I is negative
Left Axis Deviation
Lead I is most positive
Leads II and III are negative
2nd Degree Heart Block Mobitz I
Progressively prolongation of PR interval until eventually the QRS complex is dropped
Pattern repeats
2nd Degree Heart Block Mobitz II
Fixed PR interval
Intermittently dropped QRS
QRS drops tend to occur in a pattern of every 3rd or 4th P wave
Complete Heart Block
P waves and QRS complexes with no association
Healthy R wave progression
R waves should become > S waves around V3/4
Myocardial Ischaemia
ST depression of at least 0.5mm in 2 continuous leads
Previous MI
Deep Q waves that are > 25% the height of the R wave proceeding it
Normal location of inverted T waves
V1 and potentially III
Biphasic T waves may show
Hypokalaemia
Ischaemia
Flat T waves may show
Electrolyte imbalances
Ischaemia
Lateral Leads
I, aVL, V5, V6