In Right Lateral. If Δ front axis was ≥ 0°.
Or if it was < 0° but R
III ≥ 0 mV
=> Anterolateral

If not => posterolateral
p<0.0001, Sens 100%, spec 87.3%
Location of AP by Transition
Before V1
Algorithm for AP localization JACC 2013 sheinman
Left-sided
Anteroseptal:  Positive Δ in ≥ 2 inferior leads
p<0.0001, Sens 100%, Spec 100%
Anterolateral:  p<0.001, Sens 100%, Spec 100%
Positive Δ in ≥ 2 inferior leads
or
S
aVL > RaVL

If not => posterior pathway
Posteroseptal:  p<0.05, Sens 71.4%, Spec 100%
Lead I : R > S by ≥ 0.8 mV
and sum of inferior Δ polarities is negative
S
aVL > RaVL

If not => posterolateral
After V2
Right-sided
Between V2 & V3 => Right Septal

Between V3 & V4 => if Δ in II > 1 mV =>
Right Septal. If not Right Lateral
p<0.0001, Sens 97%, Spec 95%

After V4 => Right Lateral
Between
V1&V2 or at V2
Left-sided
If RI > SI by ≥ 1 mV =>

p<0.0001, Sens 100%, spec 97%

If RI > SI by < 1 mV =>
Right-sided