The brilliant two-mile chaser is favourite with Sky Bet for the Queen Mother Champion Chase at Cheltenham, having won at the Festival for the past two seasons, but he's been eased from even money to 6/4 following the news of his setback.
The seven-year-old followed up his Arkle triumph in March with an even more impressive Grade One victory against his elders in the Celebration Chase at Sandown and had been due to resume back at the Esher venue on December 9, where a potential clash with Un De Sceaux or Douvan appeared possible.
However, champion trainer Henderson, who witness another stable star Might Bite make a thoroughly satisfactory comeback when winning at Sandown on Sunday, said in a statement to Unibet that the horse has been suffering with "a wind problem" and has been ruled out.
Altior will now require a "small procedure to rectify the problem" and Sky Bet now make last year's winner Un De Sceaux their 9/4 favourite for the Tingle Creek, with Politologue 5/2, Fox Norton 4/1 and Douvan 5s.
Henderson said: "I'm really disappointed to report that Altior will miss the Grade One Tingle Creek at Sandown next month due to a wind problem that has surfaced, which means he will not be ready in time.
"He started faster work last week in the build-up to Sandown and did an excellent piece with Lough Derg Spirit last Tuesday. He was actually quite brilliant, and it is quite bizarre this has come up, as up until now he had shown no signs whatsoever that there was anything untoward.
"However, he made a whistling noise on Saturday so we did an overland scope yesterday, which is basically galloping while being scoped.
"And between our own vet Dave Matterson and Geoff Lane they both concluded that he has a small issue with his wind whereby his larynx isn't opening sufficiently so after discussing the matter with his owners, Christopher and Pat Pugh, we decided that he will need a small procedure to rectify the problem."
Henderson is still optimistic his stable star can recover in time for the Queen Mother Champion Chase at this season's Festival.
He said: "Whether we are able to fit in a prep race we don't know and only time will tell, I certainly wouldn't want to speculate.
"We can have racecourse gallops if we need too, but Altior will have a month's box rest and we'll go from there. His health is our only priority.
"We have the best advisers and surgeons ready to go and we intend to have this remedied as soon as possible, perhaps even tomorrow.
"The timing is brutal and it's tough for us all and I was only saying last week how you need luck in this game to keep all the big boys going. Sadly for us, luck has run out temporarily.
"The good news is that this horse doesn't have to retire and he will be back, make no mistake about it."
