Thanks Fathi for the nice illustration and , very good explanation. what I meant initially is a fusion between a PVC and paced and not intrinsic. I looked at the other strip and noted that there is a spike before what we called intrinsic the question i raise here is this BiV pacing? although AV delay was set very long,  is the WCT just RV pacing was device being checked? Also Discussion about antegrade conduction absolutely negates any possibility of retrograde can be debated(although I agree with your commment), i will play the devils advocate here as they say and say  it depends on the coupling interval, See this link, I don’t have the full article unfortunately 

 https://pubmed.ncbi.nlm.nih.gov/3687690/