Hi Jo,
Not really,
You do see asymmetrical vertebral waveforms from time to time and even dominant vertebral where one is huge and the other is small.
It probably just reflects an anatomical variation in the vertebral artery, the basilar artery or the circle of Willis.
The likelihood of it being a significant pathological finding in the setting you describe is low.
A very high resistance waveform with no end diastolic flow may be seen if there is a distal occlusion or a dissection, but this is not what you are seeing.
Personally I think it is fine.
Steve.