Max, 36, was admitted to A&E last December and had heart surgery and a pacemaker fitted after doctors discovered a heart block, which caused his heart to beat abnormally.
Max George was due to perform alongside bandmate Siva Kaneswaran next Thursday but will now be unable to following his secret second heart op.
He was booked in for his second operation straight away, on January 15, but was warned that the rare situation could cause a dangerous bleed on his heart.
And over the weekend he revealed he had to undergo a secret second heart operation after his pacemaker wires were inserted too deeply.
Speaking to The Sun on Sunday recently, Max opened up about his health and scary second operation.
