According to reports from the scene, Carlos Santana collapsed on stage at a concert in Michigan on Tuesday night.
His condition is not yet known, but footage showed him waving to fans as he was taken off the stage on a stretcher at the Pine Music Theatre outside Detroit.
Fans were asked to leave and to pray for Santana, who turns 75 later this month.
Santana, one of the greatest and most innovative guitar players of all time, had to cancel some dates last December due to an “unscheduled heart procedure.
“I felt like an elephant was sitting on my chest,” he later explained to the Las Vegas Review-Journal, adding that he had a 94% blockage in one artery.
Santana had to cancel more shows in February after he and others in the band developed infections.
In 1969 Santana and his band performed at the Woodstock festival, where they shot to fame.
Santana’s early hits include “Black Magic Woman,” “Oye Como Va” and “Evil Ways.
His 1999 chart-topping album, “Supernatural,” featured the song “Smooth” with Rob Thomas on vocals. The single was on top of the charts for 12 weeks and in the top 10 for 30 weeks.
Santana was ranked 11th on Guitar World’s list of the 100 greatest guitarists of all time, has won 10 Grammys for his unique fusion of rock, Latin, and jazz sounds, and was in the Rock and Roll Hall of Fame in 1998.
A documentary based on his life is in the making.