The 49-year-old illusionist was performing at his Mindfreak Live! show in Las Vegas, US, when the trick apparently went wrong.
He was dangling upside down, trying to escape from a double-straitjacket, when he passed out, according to local media.
He was lowered down in front of horrified onlookers after “spinning” on the stage for nearly two minutes, TMZ reports.
One audience member claimed the magician “stopped moving” before the curtain went down and the show was cancelled.
The incident reportedly occurred within minutes of Angel’s opening act at the Luxor hotel, where attendees feared for his wellbeing.
One wrote on Twitter: “Went to a @CrissAngel show and I think he almost died. they had to cancel the show after like 15 mins. hope he’s cool though.”
Another, Peter Sehl, posted on Facebook: “What an awful experience!
“10 mins into the show, Criss Angel was doing his upside down straitjacket stunt and was almost out after spinning for 2 mins and then they let him down.
“He stopped moving, curtain down. Break for 15 mins. Now show cancelled.
“Hope he is ok!! Didn’t appreciated peoples comments as they were leaving.”
Criss was reportedly rushed to Spring Valley Hospital Medical Center’s emergency room after “passing out” during the act.
He was discharged from the facility before 10pm, a source told TMZ.
According to one audience member, people watching the show last night were being given “full refunds” following its cancellation.
The incident comes four years after Angel suffered a shoulder injury while performing a similar stunt in New York’s Times Square in 2013.
The magician shot to fame in 2005 with his show ‘MINDFREAK’ – which made him a megastar in the US and was also screened in the UK on Channel 4.
The show earned him a massive $100 million contract to perform 10 shows a week in Las Vegas for 10 years with Cirque Du Soleil and MGM Resorts.
Last year, Angel, from New York, revealed how his toddler son, Johnny, had been diagnosed with acute lymphoblastic leukaemia.
He told People Magazine that he “felt helpless” after the two-year-old was given the devastating diagnosis in October 2015.
“My son is supposed to outlive me, I’d rather it be me that was sick,” he said.
The illusionist described how his son was technically in remission, but would keep undergoing treatment for a further two years.
Earlier this week, Angel tweeted a picture of the Luxor hotel.
He captioned the image: “Back to #vegas #mindfreakLIVE tonight! Hope to see u @LuxorLV also check out my boy @celldweller & his generous #HELP offer.”
He had previously posted footage of himself on a skiing break, including a video clip of him performing a ‘360 trick’ on a slope.
Angel is yet to issue a statement on last night’s incident.