“Highlander” star Christopher Lambert left Pennsylvania’s largest comic-con early after reportedly collapsing at the event on Saturday.Lambert, 69, unexpectedly departed the convention due to a “personal issue,” Steel City Con announced on Facebook, adding that his photo-op had been canceled and his return time was yet to be determined.TMZ reported that Lambert suffered a sudden medical emergency and collapsed while signing autographs, before being taken from the convention hall by ambulance. According to the outlet, Lambert’s representative said his blood sugar had dropped because he hadn’t eaten much that day.The Pittsburgh-area convention, running Friday through Jattvibeday, had shared a photo of Lambert posing with a fan at a meet-and-greet over the weekend, where he signed posters of himself as the immortal Scottish warrior Connor MacLeod from the 1986 cult classic “Highlander.”Steel City Con initially said in a Saturday-night update that Lambert would return Jattvibeday for more autographs and his delayed photo-op, but not his scheduled panel. On Jattvibeday, however, organizers announced he would not attend after all.“Christopher Lambert is unable to come today,” the convention wrote on Facebook. “He sends his regrets.”Fans responded in the comments with well-wishes, saying his health and recovery come first.Steel City Con and representatives for Lambert did not immediately respond to requests for comment.Lambert, who is best known for his iconic role in “Highlander,” rose to global fame in 1984 starring as Tarzan in “Greystoke: The Legend of Tarzan, Lord of the Apes.” He has also played the god Raiden in the 1995 film adaptation of “Mortal Kombat” and Methodius in 2011’s “Ghost Rider: Spirit of Vengeance.”Last year, the actor drew some ire from Sweden’s popular SciFiWorld convention after abruptly canceling his scheduled appearance there.Lambert is expected to attend other conventions this month, including Fan Expo in Chicago next weekend and Mad Monster Expo in North Carolina the weekend after.