Cammy Devlin was one of the scorers as they stormed back to earn the victory that will ensure the Edinburgh side will finish in the top four of the Scottish Premiership and again play in UEFA competition next season.
Devlin, Kye Rowles and Nathaniel Atkinson were all starters in the dramatic contest at Tynecastle as Hearts, in third place in the league behind the Old Firm of Celtic and Rangers, were shocked to go two down to the basement club Liv within 22 minutes thanks to Stephen Kelly's brace.
But Hearts, who didn't risk Calem Nieuwenhof after a recent injury, produced a brilliant response to score four before the interval.
Jorge Grant and Yutaro Oda had brought the sides level before midfielder Devlin struck, latching on to Alex Cochrane's low pass from the left to squeeze the ball home and give Hearts the 3-2 lead.
Captain Lawrence Shankland got a fourth before halftime to ensure that Hearts remained 11 points clear in third place, and can now not finish lower than fourth in the Premiership.
It was reason for celebration too for their beloved veteran goalkeeper Craig Gordon, who played in a league match for the first time since Christmas Eve 2022 at the age of 41.
The Australian trio will hope to be included in next weekend's Scottish Cup semi-final with Rangers in what's proving a tremendous season for the Jambos.Â
Inevitably, they have become known as the 'Jamboroos', with the on-loan Garang Kuol having also been in their ranks last season.
Their next aim will be to ensure they finish in third spot, to get into the Europa League or Europa Conference League group stages.
Champions Celtic, trying to emulate their success under Ange Postecoglou, moved four points ahead of Rangers at the top with a 3-0 victory at home to St Mirren.
Midfielder Reo Hatate recorded his first goal for six months with his fellow Japanese Kyogo Furuhashi and then Adam Idah also netting.
