According to Official Guinness Records,
The longest videogames marathon playing a card game lasted 30 hours exactly and was achieved by Laura Rich (UK) and Kathleen Henkel (USA), who played Solitaire Blitz (PopCap, 2012) simultaneously in London, UK, and New York, USA, respectively on 26-27 June 2012.
For a complete list of 2012 records, please visit 2012 Guinness Records in United Kingdom.