EKG cheat sheet - EKGs made easy
Nursing - CTE (Stafford High School)
, RATE SHARP J POINT
300 150 100 75 60 50 43 • ST seg. & T wave well demarcated, not merged as in STE
• J point elevation is normal in young, healthy athletes
DIFFUSE J POINT
• ST slowly curving with only an area J point can be found
- Count number of complexes x 6 (standard ECG = 10sec)
RHYTHM ST SEGMENT ELEVATION
• Locate the P wave (rate, axis, morphology) (New STE at the J point)
• What is the relationship between the P wave and QRS? In all leads (except V2-V3), significant STE =
• Analyze QRS morphology In two contiguous leads
AXIS DEVIATION Lead I QRS Lead II/aVF QRS In leads V2-V3, significant STE =
Normal (-30 to 90º) + +
Left + -
Right - + ≥0.25mV in men ≤40yo
ST SEGMENT DEPRESSION
HYPERTROPHY (New horizontal or down-sloping STD)
• LEFT ATRIAL ENLARGEMENT (P mitrale) Significant STD =
• P wave > 0.12sec and bifid in lead II In two contiguous leads
• RIGHT ATRIAL ENLARGEMENT (P pulmonale)
LAE RAE
• P wave > 0.25mV in lead II
T-wave inversion ≥0.1mV in two contiguous leads with
• LVH Prominent R wave or R/S ratio>1
• R wave in V5 or V6 >25mm
• S wave in V1 or V2 >25mm
• Sum of R wave in V5 or V6 + S wave in V1 >35mm
• RVH PATTERNS
• R wave > S wave in V1
WAVES, INTERVALS, & SEGMENTS
R
5mm=0.2sec(200ms)
ST segment
P 1mm Dominant R waves in leads V1-V3
=0.1mV LVH RVH ST depression in V1-V3
T Upright, tall T waves
STEMI EVOLUTION
1mm= Hyperacute T waves (tall, peaked,
0.04sec(40ms) symmetric)
Q S STE in contiguous leads (concave →
0.12s<PR<0.2s convex, merging with T wave)
Development of Q wave and T wave
QRS<0.12s inversions as ST returns to baseline
QTc interval99%ile QTc
QT<(1/2)RR Prepuberty 1-15yo460ms
M W
www.henrydelrosario.com
Normal 0.44 <0.43 <0.45
NORMAL INVERTED T WAVES HYPERKALEMIA BBB
QTc=QT/sqr(RR) Postp Males 470ms
Prolonged >0.46 >0.45 >0.47
Postp Females 480ms
(upper 1%)
NORMAL Q WAVES V1: “M”
• Small (septal) q waves normal in leads aVL, I, II, V5, V6 INVERTED T WAVES IN ISCHEMIA V6: “W”
• Can be normal on expiration in lead III
PATHOLOGICAL Q WAVES (PRIOR MI) ≥0.1mV in two contiguous leads
TALL T WAVES
• >1-2 small squares deep (or >25% of R wave)
• >1 small square wide (or ≥30ms) V1: “W”
LVH → LV STRAIN PATTERN → TWI in leads I, aVL, V5-6 V6: “M”
• More likely diagnostic if with inverted T wave Q
RVH → RV STRAIN PATTERN → TWI in leads II, III, aVF
DOMINANT R WAVE
• In lead V1: normal in young children; seen in RVH, RBB, HCM, posterior MI SOURCES: ECG tutorials on UpToDate (Basic principles of ECG analysis, Myocardial ischemia and infarction),
• In lead aVR: TCA poisoning, dextrocardia, VT Making Sense of the ECG by Houghton, Pocket Medicine by Sabatine; Third Universal Definition of Myocardial
POOR R WAVE PROGRESSION Infarction by Thygesen et al; lifeinthefast lane.com; compiled by Henry Del Rosario MD; last update 5/2018
• Prior anteroseptal MI, cardiomyopathy, LVH, RVH/COPD, LBBB
Nursing - CTE (Stafford High School)
, RATE SHARP J POINT
300 150 100 75 60 50 43 • ST seg. & T wave well demarcated, not merged as in STE
• J point elevation is normal in young, healthy athletes
DIFFUSE J POINT
• ST slowly curving with only an area J point can be found
- Count number of complexes x 6 (standard ECG = 10sec)
RHYTHM ST SEGMENT ELEVATION
• Locate the P wave (rate, axis, morphology) (New STE at the J point)
• What is the relationship between the P wave and QRS? In all leads (except V2-V3), significant STE =
• Analyze QRS morphology In two contiguous leads
AXIS DEVIATION Lead I QRS Lead II/aVF QRS In leads V2-V3, significant STE =
Normal (-30 to 90º) + +
Left + -
Right - + ≥0.25mV in men ≤40yo
ST SEGMENT DEPRESSION
HYPERTROPHY (New horizontal or down-sloping STD)
• LEFT ATRIAL ENLARGEMENT (P mitrale) Significant STD =
• P wave > 0.12sec and bifid in lead II In two contiguous leads
• RIGHT ATRIAL ENLARGEMENT (P pulmonale)
LAE RAE
• P wave > 0.25mV in lead II
T-wave inversion ≥0.1mV in two contiguous leads with
• LVH Prominent R wave or R/S ratio>1
• R wave in V5 or V6 >25mm
• S wave in V1 or V2 >25mm
• Sum of R wave in V5 or V6 + S wave in V1 >35mm
• RVH PATTERNS
• R wave > S wave in V1
WAVES, INTERVALS, & SEGMENTS
R
5mm=0.2sec(200ms)
ST segment
P 1mm Dominant R waves in leads V1-V3
=0.1mV LVH RVH ST depression in V1-V3
T Upright, tall T waves
STEMI EVOLUTION
1mm= Hyperacute T waves (tall, peaked,
0.04sec(40ms) symmetric)
Q S STE in contiguous leads (concave →
0.12s<PR<0.2s convex, merging with T wave)
Development of Q wave and T wave
QRS<0.12s inversions as ST returns to baseline
QTc interval99%ile QTc
QT<(1/2)RR Prepuberty 1-15yo460ms
M W
www.henrydelrosario.com
Normal 0.44 <0.43 <0.45
NORMAL INVERTED T WAVES HYPERKALEMIA BBB
QTc=QT/sqr(RR) Postp Males 470ms
Prolonged >0.46 >0.45 >0.47
Postp Females 480ms
(upper 1%)
NORMAL Q WAVES V1: “M”
• Small (septal) q waves normal in leads aVL, I, II, V5, V6 INVERTED T WAVES IN ISCHEMIA V6: “W”
• Can be normal on expiration in lead III
PATHOLOGICAL Q WAVES (PRIOR MI) ≥0.1mV in two contiguous leads
TALL T WAVES
• >1-2 small squares deep (or >25% of R wave)
• >1 small square wide (or ≥30ms) V1: “W”
LVH → LV STRAIN PATTERN → TWI in leads I, aVL, V5-6 V6: “M”
• More likely diagnostic if with inverted T wave Q
RVH → RV STRAIN PATTERN → TWI in leads II, III, aVF
DOMINANT R WAVE
• In lead V1: normal in young children; seen in RVH, RBB, HCM, posterior MI SOURCES: ECG tutorials on UpToDate (Basic principles of ECG analysis, Myocardial ischemia and infarction),
• In lead aVR: TCA poisoning, dextrocardia, VT Making Sense of the ECG by Houghton, Pocket Medicine by Sabatine; Third Universal Definition of Myocardial
POOR R WAVE PROGRESSION Infarction by Thygesen et al; lifeinthefast lane.com; compiled by Henry Del Rosario MD; last update 5/2018
• Prior anteroseptal MI, cardiomyopathy, LVH, RVH/COPD, LBBB
