Various
diseases and ECG criteria
The following are some heart diseases, with their most
significant ECG criteria.
The sense of these notes is to be able to identify a
disease beyond the clinic, by the only electrocardiographic signals.
Anterior
subendocardial Ischemia
- T waves high and negative on I, II, aVL, V5, V6
Acute pulmonary
embolism
- S wave in I, aVL
- Q in III
- T neg in III, aVF
- Complete or incomplete RBBB
- Low Voltage on Lead limbs
Atrial septal
defect (ASD)
Right ventricular overload with:
- Complete or incomplete Right bundle branch block
(RBBB)
- Right Axis Deviation
Apex Myocardial
Infarction
- Q wave in I, II, III
Anteroseptal
myocardial Infarction
- ST above + Q waves in V1-3
- T neg. in V1, 2, aVL
Anterior
myocardial infarction
ST elevation in V2, 3.4
Anterior/Left
Myocardial Infarction
- ST elevation and (maybe) Q waves in V4-6
Biatrial
hypertrophy
- Leads I and II have an early, pointed, and bifid P.
- V1 observe in the first half 'of diphasic P' right
atrial hypertrophy associated with subsequent significant negativity of the left atrial hypertrophy
Dextrocardia
(or inversion of limb leads)
- P neg.in I
- P pos. in II, III
Digitalis
effect
- Depression of the ST segment in V4
Hyperkalaemia
Potassium> 5.5:
- T wave high and pointed in V3, 4.5
- Slightly widened QRS
Potassium> 6.5:
- !st degree AV Block
- ST depression
- Wide QRS
- P waves barely visible, flat.
Potassium> 7.5:
- P waves are absent
- RBBB, LBBB, Ventricular Tachycardia, Ventricular
Fibrillation, asystole.
Hypercalcemia.
- Shortened QT interval (V2)
- J Wave
Hypokalemia
- ST segment depression
- Flattening of the T wave
- Appearance of U wave in V3-6
- Supraventricular tachycardia
- Atrial ectopic beats
Hypocalcemia.
- Prolonged QT interval (II, 0.52 sec.)
Inferior
Myocardial Infarction
- ST elevation in II, III, aVF
- ST depression in I, aVL and precordial leads.
Juvenile type
ECG (max 30 years)
- T wave inverted (negative) in V1, V2, V3, V4.
- ST-segment elevation
- Tall T-wave.
Left atrial
hypertrophy (LAH)
("mitral P wave" because the disease is
present in the case of mitral stenosis).
- P waves wide (> 120 ms) and bifid in I
- Bifid P wave in V1 very deep negative
Left Axis
Deviation
- Typical in old people, obesity
- Left anterior fascicular block
- 50% Left ventricular hypertrophy (LVH)
Left high
Myocardial infarction
- ST elevation in I, aVL
Left Myocardial
infarction.
- St segment elevation and (maybe) Q waves in I, aVL,
V5, V6
Left
ventricular hypertrophy (LVH)
- Left Axis Deviation
- R> 25 mm (5 squares) in V5 or V6
- S> 25 mm (5 squares) in V1 or V2
- left atrial Hypertrophy
- ST-segment depression (I, V5, V6) and negative T
wave
Sokolow-Lyon index:
- SV1 + (RV5 or RV6)> 3.5 mV
- R in aVL> 1.1 mV
Cornell voltage criteria
S wave in V3 + S wave in aVL ≥ 2.8 mV (for men)
S wave in V3 + S wave in aVL ≥ 2.0 mV (for
women)
Low voltage in
all leads.
- Are observed in the case of obesity, exudative
pericarditis, Myocardial infarction, Chronic obstructive pulmonary disease
(COPD) or old people.
Old inferior
infarction (diaphragmatic)
- Q wave in II, III, aVF
- T waves neg. and deep
- ST isoelectric (normal)
Posterior
Infarction
- High R waves on V1-V3
Pericarditis
Acute phase:
- ST segment elevation in all leads
Subacute-chronic:
- negative T (No ST)
Low voltage in case of massive effusion or
constrictive forms.
Right Axis
Deviation
- Typical in young and lean people.
- Sudden onset of Right Axis Deviation could be
embolism or pulmonary infarction.
- left posterior fascicular block (LPFB)
Right
myocardial infarction
- ST elevation in V1-3
Right atrial
hypertrophy (RAH)
(Right atrial overload by tricuspid stenosis or
pulmonary hypertension).
- P waves high (> 2.5 mm) and pointed in II, III,
aVF, V1
Right
ventricular hypertrophy: (RVH)
Right-Axial Deviation
-QRS negative in I
-QRS positive in V1
-ST-segment abnormalities in V3-V1-aVF-I (QRS-T angle
very large (> 60)
Subendocardial
ischemia
- High T Positive wave in the ischemic zone
Subepicardial
ischemia
- neg. deep and symmetrical T in the ischemic zone
- T and QT normal or slightly elongated
Ventricular
Aneurysm
- ST segment elevation in V2
- Inverted T wave in V2
…