ECG quick Flashcards
sinus rhythm
- P wave before every QRS
- P wave with sinus morphology
- Positive in I, II, aVF, negative in aVR
- HR 60-100 bpm
Heart axis
- I + aVF +
- > 0-90 degrees (normal axis)
2. I+ aVF - II + -> 0-(-30) degrees (normal axis) II - -> -30-(-90) degrees (LAD -> left-axis deviation)
- I - aVF +
- > 90-180 degrees (RAD -> right-axis deviation) - I- aVF -
- > -90-(-180) degrees (EAD -> extreme-axis deviation)
P wave duration + amplitude
≤ 0.12 s
amplitude -> normally no more than: 1. 0.25mV in frontal plane leads 2. 0.3 mV in precordial leads 3. V1: positive ≤0.15 mV negative ≤0.1 mV
PR duration
adult: 0.12 to 0.20 s
QRS duration
0.07-0.11 s
Direction of QRS
- Always should be positive in:
1) I, II
2) aVL
3) V4, V5, V6 - Should be negative in
1) aVR
2) V1
3) V2 - In other (III, aVF, V3) can be either
Significant elevation of ST -> norms
1) in V2 and V3
1. Women ≥0.15 mV
2. Men <40 years: ≥0.25 mV
3. Men ≥40: ≥0.2 mV
2) in other leads: ≥0.1 mV
3) Measured in point J
Significant decrease of ST -> norms
- V1, V2, V3 ≥0.05 mV
- Other leads ≥0.1 mV
- Measured in point J
T wave amplitude
1) shouldn’t exceed 0.6 mV in limb leads
2) shouldn’t exceed 1.0 mV in precordial leads
QTc duration
≤ 0.46 s
right atrial enlargement
- peaked proximal part of P wave (A-like appearance)
- > it’s called P PULMONALE - Amplitudes of P wave: >0.25 mV in II or > 0.15 mV in positive phase of V1
left atrial enlargement
Duration of P wave > 0.12s in II or
Increase in duration (>0.04s) and amplitude (0.1 ms) of negative phase of P wave in V1
Left ventricular enlargement suggestion
V1 -> increase in S (QS) wave amplitude
V6 -> increase in R amplitude
I and aVL-> increase in R wave amplitude
Cornell criteria: R wave in aVL + S wave in V3:
⩾ 2.8 mV in males
⩾ 2.0 mV in females
Right ventricular enlargement suggestion
V1 -> increase in R amplitude
V6 -> increase in S amplitude
R>S in V1
S>R in V5 or V6
RBBB
- > all
1. QRS ≥ 0.12 s (incomplete ≥ 0.11 s)
2. V1 or V2: M-shaped QRS (RSR’) and
3. I and V6: S wave wider than R wave or ≥ 0.04 s)
4. Possible changes of ST (oblique decrease) and T (negative) -> V1, V2, V3 - > (if not -> consider myocardial infarction)
5. Late intrinsicoid in V1 R’ peak or late R peak, >0.05 s
LAFB
- Left axis deviation (-45 to -90 degrees)
- Small Q (qR) in aVL and I
- Small R (rS) in III and aVF
- QRS <0.12 s
- Late intrinsicoid deflection in aVL >0.045 s (qR)