Sacre is 'perfectly normal'
Sprinter Sacre pleased Nicky Henderson and equine heart specialist Celia Marr when cantering at Seven Barrows on Friday morning
The highest rated chaser in training had been pulled up at Kempton in the Desert Orchid Chase on 27 December and was found to have been suffering with an irregular heartbeat.
He returned to his trainer Nicky Henderson's stables that evening before being taken to Newmarket for assessment by Marr the following day.
Marr confirmed the original diagnosis of atrial fibrillation and decided to give the horse some time to see if his heartbeat regulated itself which it did.
Henderson has now reported Sprinter Sacre's heart rate to be "perfectly normal" after his charge came through a crucial workout on his first canter since at Seven Barrows, during which he was monitored closely with ECG equipment.
Henderson said: "We can't tell an awful lot at this stage, but his heart was normal this morning and remained so through exercise. Everyone was happy and everything looked perfectly normal."
Sprinter Sacre is now set to continue in light work and Henderson is not ruling out the possibility of the eight-year-old defending his crown in the Bet Victor Queen Mother Champion Chase at the Cheltenham Festival in March.
"What I know about hearts and heartbeats and all these things you could write on a postage stamp, but the good news is that he self-righted," he told Racing UK.
"If he'd needed treatment with drugs, we would probably have had to write off this season.
"Nobody is writing it in at this stage, we'll have to see about that. We may have seen the end of this episode, we'll need to monitor him from this point and Celia will be back to do the same thing again in the future.
"The horse looks great, Nico [de Boinville, his regular rider at home] says he feels great. There's a lot of water still to go under the bridge but we've got a chance.
"He'll come back into a normal routine. There's only any point in him coming back if we can get him back for the Queen Mother. There are lots of other races, but my gut feeling is that we weren't going to get him back for Cheltenham, we wouldn't bring him back this year."
Nicky Henderson can be backed at 5/4 with Sky Bet to retain his trainers' championship title this season, with Paul Nicholls a 4/6 chance.