Direct Airside Transit Visa Exempt?

[bellerophon]

I am an Indian citizen I will be travelling to New York JFK via London Heathrow. My flight would be arriving at terminal 5 and departing from terminal 3 at Heathrow. I have a valid 10 year multiple entry B1/B2 visa for the US. My question is do we have to go through passport control at heathrow? Also, am I exempt from DATV or do I have to get one? Could there be any problems at the airport coz I have hear some people getting stuck at airport due to visa issues?

Thanks in advance.

[cafeconleche]

You're exempt with your US visa.