Band-mates Gene Simmons, Tommy Thayer and Eric Singer played the Friday night gig at Soboba Casino, about 90 miles east of Los Angeles, as Stanley was taken to the hospital.
"During sound check yesterday, my heart spontaneously jumped to 190 plus beats per minute where it stayed for over an hour necessitating paramedics to start an IV and give me a shot to momentarily stop my heart and get it into a normal pattern," Stanley said in the Saturday Web site posting.
"Not knowing if this episode was life threatening made it even more exhausting," the statement continued.
Phone and e-mail messages for KISS manager Doc McGhee seeking comment about Stanley's condition were not immediately returned Saturday night.
It was KISS' first ever appearance as a trio, according to the band's Web site.
As famous for their makeup, stage mayhem and wagging tongues as their music, KISS recorded the 1970s hits "Rock and Roll All Nite" and "Detroit Rock City."
The 55-year-old Stanley, born Stanley Eisen, released a solo album, "Live to Win," in 2006.