The Aston Villa manager is clear of immediate danger after last week's chest pains, but his condition - a dissection of the descending aorta - was similar to that which resulted in 11 hours of open heart surgery a decade ago, when he was in charge at Liverpool.
Dr Mark Waller, who worked with Houllier at Anfield and now has a similar role at Villa, said: 'All tests have confirmed Gerard's heart is working perfectly.'
On the mend? Houllier is leaving hospital but medics have cast doubt over his future as a football manager
However, medics contacted by Sportsmail have doubts. One said: 'The problem is in such an awkward position that it is difficult to carry out surgical work. The most likely outcome is that Mr Houllier would be treated by medication.
'It would be difficult to believe that he would not be advised strongly to stay away from high-stress professional commitments.'
Houllier said: 'My condition is improving and extremely encouraging. I'm touched by all the messages. It has been overwhelming.'
Gone but not forgotten: Villa staff leave Houllier's space on the bench free
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Source: Daily Mail
Source: Daily Mail