Huntsworth last summer merged GCG with Citigate Public Affairs, which it inherited as a result of the acquisition of Incepta.
Lvovich worked originally for Ergo Communications, which GCG acquired in July 2004.
Her deputy Rocco Renaldi has assumed her London-based role for the foreseeable future, reporting to vice-chairman Warwick Smith.
Lvovich's hire comes as APCO was this week appointed by the Motor Accident Solicitors Society to assist its campaign to protect the legal rights of individuals who suffer personal injury in vehicle accidents.
Currently, personal injury cases that award claimants more than £1,000 allow for legal costs to be recovered from defendants who are found liable. But the Government is considering raising the bar to £5,000.
Miller said such a move would 'let the people who cause motor accidents – and their insurance companies – off the hook and relegate the interests of the innocent'.