The actor's 16-year-old son was taken to a local hospital after the incident in January (09), which took place during a family holiday.
Former Bahamian Senator Pleasant Bridgewater and paramedic Tarino Lightbourne, who attended to the boy after the attack, are currently on trial in the Bahamas on charges of extortion.
They are accused of conspiring to release a document containing information about Jett's death in a $25 million (£17.2 million) bribery plot against Travolta and his grieving wife Kelly Preston.
Travolta took to the stand on Wednesday (23Sep09) and described how his children's nanny woke him up in a panic on the fateful morning to alert the star to his son's condition.
The actor told the court how one of Jett's caretakers tried to revive the boy with chest compressions, before Travolta stepped in to take over CPR. His efforts failed to revive his son, who was taken away in an ambulance.
During his testimony, Travolta admitted his son was autistic, revealing he suffered seizures lasting between 45 seconds to one minute every five to 10 days.
Travolta told the court, "He was autistic. He suffered from a seizure disorder."
On Tuesday (22Sep09), the Bahamas court heard testimony from police inspector Andrew Wells, who claimed Lightbourne had told him the actor initially wanted to fly his son to Florida so he would receive better medical care. He allegedly changed his mind soon afterwards and instructed the paramedics to take the teen to a local hospital, where he was later pronounced dead.
Bridgewater and Lightbourne have pleaded not guilty to the allegations. The trial continues.