Ventricular hypertrophy produces changes in one or more of the following areas: the QRS axis, the QRS voltages, the R/S ratio or the T axis.
Right ventricular hypertrophy
Axis: RAD for the patients age
Voltages:
- V4R / V1: Increased anterior forces (increased R waves greater than limits for patient’s age)
- V5 / V6: Increased rightward forces (increased S waves greater than limits for patient’s age)
R/S ratio: Abnormal R/S ratio in favour of RV
- V1, V2: R/S ratio greater than upper limits for child’s age
- V6: R/S ratio less than 1 after one month of age
V4R, V1: upright T waves in children 3 days to 6 years (provided T is normal elsewhere ie upright in V6) – evidence alone of significant RVH
V1: q wave
Left ventricular hypertrophy
Axis: LAD for the patients age (marked LAD is rare with LVH)
Voltages:
- V4R / V1: Increased posterior forces (increased s waves greater than limits for patient’s age)
- V5 / V6: Increased leftward forces (increased R waves greater than limits for patient’s age)
R/S ratio: Abnormal R/S ratio in favour of LV
- V1, V2: R/S ratio less than upper limits for child’s age
V 5/6: Q wave ≥ 5mm
1 / aVF: inverted T wave (‘strain’)
Biventricular hypertrophy
- Positive voltage criteria for RVH and LVH (with normal QRS duration)
- Positive voltage criteria for RVH or LVH and relatively large voltages for other ventricle
- Large equiphasic QRS complexes in two or more limb leads and in mid‐precordial leads (V2‐5)
