rS-waveform is
observed.
Lead V1 - Bundle branch blocks are usually seen in Leads V1,
V6 and sometimes V2. The first wave of depolarization toward lead
V1 results in a short r-wave, referred to as a "septal R-wave".
It represents septal depolarization. The second wave of
depolarization is away from lead V1 and is represented by an
S-wave, due to the large amount of conduction taken away by the
left ventricle. Under normal conditions the rS-waveform is
observed.
Lead V6 - The first wave of depolarization travels away from
lead V6. It is represented by a short q-wave, also referred to as
a "septal q-wave". The second wave of depolarization travels
toward lead V6. It is represented by a positive deflection of an
R-wave due to the large amount of electrical conduction to the
left ventricle. Normally seen is a 
qR-wave form.