Mr McDaid, 63, a co-founder of the company he led to flotation in 2001, stepped down in November 2002 as the heart valve maker's losses mounted. But he reappeared as a non-executive in 2005, the year after the company closed its headquarters in Bellshill, North Lanarkshire, which at its peak had employed 200.
In April 2011 Mr McDaid almost became a Liberal Democrat candidate for Holyrood but drew back amid a row over his donations to the party. Four months later, he was appointed finance director as AorTech moved its base from Australia to the US.
In 2012 AorTech had to raise emergency funding to fight US litigation over its patents by its principal customer St Jude Medical.
Two months ago chairman Bill Brown, a former fund manager at F & C in Edinburgh, announced a deal with Biomerics of Salt Lake City for the manufacture and distribution of its patented Elast-Eon and ECSil materials, and the supply of polymer to AorTech's licensees.
Mr Brown said yesterday that the company was transitioning from a medical polymer manufacturing business to a "pure play intellectual property exploitation company". He said: "Within the next month AorTech will cease all operations in the US, including manufacturing, which will result in cost savings due to the significantly lower cost base in the UK."
In the transition, chief executive Frank Maguire decided to resign with immediate effect to pursue other business opportunities, after 13 years on the board.
Mr Brown paid tribute to Mr Maguire's contribution especially in the past year, and said Mr McDaid would become CEO with immediate effect. "Over the past year, Eddie has become much more actively involved in all client related issues and as a result, we anticipate an orderly handover."
Non-executive Roy Mitchell, a chartered accountant with international taxation expertise, would replace Mr McDaid as finance director.
AorTech's shares, which sank to 44p in July, have risen by 61% since the deal with Biomerics was unveiled on October 1.
Yesterday, shares fell 2p, to 124p, to value the company at around £6m.