He described talks over the issue as "difficult and hair-raising at times"
Junior Minister John Halligan says he would have resigned if a new mobile cardiac unit was not delivered for Waterford.
The new mobile catheterisation lab is being set up to deal with the backlog of cardiac patients at University Hospital Waterford.
The Independent Alliance TD says the Health Minister Simon Harris has agreed to the new unit - despite reports that the hospital management had favoured outsourcing the treatment to Cork.
The Independent Alliance TD had previously indicated he would have to resign if the Government did not come up with a proposal he was happy with.
Consultants from the south east last year "utterly rejected" the findings of a Waterford Hospital report, which did not recommend a second cath lab at the hospital.
Deputy Halligan says a mobile unit should now be in place in a matter of weeks.
He said the meetings over the issue with the Department of Health continued into Thursday night.
"It was difficult and hair-raising at times the meetings we had all through yesterday up to 10 o'clock last night - with my advisers and PRs and so on dealing with Simon Harris'.
"But the Government has decided that a mobile lab will be placed in Waterford very shortly - we're hoping within a few weeks"
Speaking to WLR FM, Deputy Halliagn says without this plan he would not have stayed in Government with Fine Gael.
"If he'd have told me no, I would have gone today - I indicated that to the Independent Alliance.
"I have to be honest that if there was no mobile lab, I would see no future for me in Government".