Published Monday, 21 April 2014
Fitzpatrick suffered an irregular heartbeat during the Glasgow game. (© Presseye)
The club said the prop has been discharged from hospital following treatment to correct the issue and will return to Belfast to undergo further tests.
Ulster have not said how long Fitzpatrick, 30, will be out for.
Meanwhile, Ricky Lutton sustained an injury to his toe in the defeat against Glasgow, however, x-rays have shown there is no break.
He will have ongoing physiotherapy ahead of the Leinster game.
Tom Court is expected to resume training this week after suffering a thumb injury, which scans also confirmed was not broken, in the game at Scotstoun.
Following the weekend's action, Ulster are third in the RaboDirect Pro12, three points behind Munster and nine behind leaders Leinster.
Ulster face Leinster in the penultimate game of the season at Ravenhill on Friday 2 May before travelling to Thomond Park to face Munster on Saturday 10 May.
© UTV News