Catherine Bonner, 55, died on 14 February 2013, after the lorry, driven by George Marshall, smashed into the side of her house.
Her partner, Jim McColl, was badly injured in the crash.
Mr Marshall was initially reported to the procurator fiscal for causing her death by dangerous driving, however the Crown Office decided against pursuing the case.
At Kilmarnock Sheriff Court, Scotland, it was heard that the driver suffered an explosive coughing fit moments before the crash in Fairlie, North Ayrshire.
Catherine’s family were present for the beginning of the inquiry into her death.
The court yesterday heard from one witness who was driving behind the lorry before it crashed into the house.
William McCrindle, 77, a retired businessman, was driving to his home in West Kilbride, North Ayrshire on the day of the crash.
He said: “The truck took a direct line straight down the road, straight into the house.
“It was almost like a disaster movie, there was a colossal bang.
“I parked the car and rushed up quickly to the house. The gap between the wall and house was narrower than the truck.
“The house was made of heavy sandstone and a pile of bricks was lying in the road.
“A pedestrian told me there was a lady lying under the debris.
“The first thing I did was phone 999 and said ‘I need the fire brigade, police and ambulance right away’.”
Mr McCrindle said that the lorry was embedded so far into the house that he was sure the driver had been killed.
The pensioner then directed traffic around the debris in the road until the emergency services arrived within five minutes of the call.
The court also heard from Dr Peter Bloomfield, 64, a consultant cardiologist from Edinburgh, who examined Mr Marshall in 2014.
He told the court: “The account [Mr Marshall] gave me corresponded exactly with what he said earlier.
“He was driving his fully loaded lorry and he had an explosive coughing fit.
“He saw himself crash into the wall, he remembers someone helping him out of the cab.”
He confirmed Mr Marshall seemed “entirely credible” and that there were no inconsistencies in his history. Mr Marshall is due to give evidence at the inquiry today.