By GEORGE A. PAUL / CONTRIBUTING WRITER
As Kings of Leon took the stage Saturday night at the Forum, the sight and sound of a beating heart projected on two screens signaled their arrival.
Fittingly, if anyone bothered to measure the Nashville-based rock band’s career pulse, it would be considered strong by most accounts. Last fall, its seventh album, “WALLS,” debuted atop the Billboard 200 (a career first). The single “Waste a Moment” reached No. 1 on alternative, rock and adult album alternative radio and still crowns the latter chart after 15 weeks.
Saturday’s sold-out show from the Followill family capped a brief North American tour. Obscured by shadowy red lights, Kings of Leon kicked off the 100-minute, 25-song concert with a moody “The End,” off 2010’s “Come Around Sundown.” It was driven by Matthew’s…