Get the latest entertainment news, reviews and star-studded interviews with our Independent Culture email Get the latest entertainment news with our free Culture newsletter Get the latest entertainment news with our free Culture newsletter The West Wing actor Mary McCormack is stepping in for Joe Mantegna to co-host the National Memorial Day Concert in a last-minute change. McCormack, 57, will lead the 37th annual concert with Forrest Gump actor Gary Sinise, after Mantegna, who has hosted the annual concert for nearly two decades, dropped out of PBS’s TV event due to what the Tony-winning actor described as “unforeseen circumstances.” “I truly wish I could be there in person this year but due to unforeseen circumstances, I need to remain in Los Angeles,” Mantegna said in a statement. “I’m looking forward to joining the millions of Americans watching this Sunday’s concert on PBS and continuing to do everything I can to support this important event for years to come.” Capital Concerts announced the hosting shake-up days after confirming that Mantegna and Sinise — who first co-hosted …