Autopsy finds Admire Rakti died of 'acute heart failure': Racing Victoria Agony and ecstasy: Admire Rakti barrels down the back straight on his doomed Melbourne Cup run. Acute heart failure has been identified as the cause of the death of Melbourne Cup favourite Admire Rakti in the minutes after the race on Tuesday as the horse's devastated owner spoke of his grief. Owner Riichi Kondo said through an interpreter on Wednesday morning the champion stayer "has been a great and fantastic horse for us." "We are very proud but yet we are so very, very upset," Kondo said. Everyone associated cannot believe what has happened and we are genuinely thankful for the help from the Australians for all the time that we are here but also deeply thankful for the many, many hundreds of well wishes that our group has received since the tragic death of Admire Rakti. Admire Rakti brought great, great fame to our country by winning the Caulfield Cup, but yet we are understandably shattered by what has happened. Racing Victoria's chief veterinarian Brian Stewart told SEN Radio on Wednesday that an autopsy conducted at the University of Melbourne showed that the Japanese stayer, which dropped back through the field in the latter stages of the race, suffered from ventricular fibrillation. "The diagnosis is that the horse died of acute heart failure as a result of ventricular fibrillation probably, which is a disorganised heart rhythm which happens very, very rarely in human athletes and in horses and is a consequence of the athletic heart and the rapid heart rate during racing," Dr Stewart said. It is very rare but it does occur. It's a disruption of the normal electrical conduction through the heart and there can be various sets of circumstances that might set it off. Athletes are probably more prone to the syndrome especially those with large hearts and a big capacity to raise the heart rate . . . throwing it into this abnormal rhythm and the heart is unable to supply enough blood for the body. Admire Rakti was one of two horses that died after the Melbourne Cup. Seventh-placed Araldo was euthanased after breaking its leg when it hit a fence on its way back to its stable after being spooked by a young child waving a flag. Racing Victoria chief steward Terry Bailey said the results from the full autopsy would be available next week. He reiterated that all horses for the race were fully vetted by the "best veterinarians" and that the Japanese connections were "still stunned this morning." Admire Rakti's entourage were given a room at Flemington on Tuesday so that they could come to terms with the death of the horse. with Patrick Bartley