First Minister Peter Robinson is expected to be discharged from hospital inside the next 24 hours.
Sources close to the DUP say their party leader, who suffered a suspected heart attack earlier this week, could be home later today.
Shortly after he was rushed to the Royal Victoria Hospital in Belfast health officials said 66-year-old Mr Robinson underwent a "procedure" on Monday.
It's now understood that at least one stent was used in Mr Robinson's treatment.
A stent is a wire mesh stainless steel tube that holds an artery open and keeps it from closing again, becoming a permanent part of the artery.
Mr Robinson first became ill during a cycle ride with a party colleague.
The DUP leader had recently taken up cycling to improve his health but had to stop twice during a ride with Sammy Douglas last Saturday complaining of tiredness.
The two men had been out cycling together for the last two weekends.
However, Mr Douglas noticed that his leader was more tired than the week before.
"Last Saturday he had to stop twice," he said.
"I thought at the time he was just tired and he said he had a spot of indigestion, soreness around the chest or stomach it sounded like. But he was in the best of humour."
He became more ill on Monday morning and was rushed to hospital.
Deputy First Minister Martin McGuinness visited Mr Robinson at the RVH on Wednesday night and took him a bowl of fruit.
He said at the time: "Hopefully he's on the mend. I would hope he will be out of hospital very shortly."
Finance Minister Arlene Foster was among Mr Robinson's other visitors at the Royal where he has been under police guard ever since he was transferred to a specialist cardiac ward there from the Ulster Hospital near his Dundonald home.
Mr Robinson's health problems meant he missed a contentious debate in the Assembly on welfare reform.
Sinn Fein and the SDLP blocked the passage of legislation which would have allowed the Stormont Executive to implement changes in the benefits system.
Senior party colleagues visited him in hospital and briefed him on events in the Assembly.