The French giants beat the Catalan team 4-0 in the first-leg of the last-16 tie, but were beaten 6-1 at the Nou Camp to exit in the first knockout round.
Cavani and his team-mates were advancing to the quarter-finals until the very last minute when substitute Sergi Roberto’s 95th minute winner completed a stunning comeback.
Barca were 5-3 down on aggregate in the 88th minute before two quick-fire goals from Neymar – a future team-mate of Cavani in Paris – set up a tense injury time that ended with PSG bowing out in spectacular fashion.
In an interview with ESPN, Cavani admitted that the game impacted on his life for some time.
The 32-year-old said: “This game touched me a lot. Nobody imagined what could have happened.
“I was unable to sleep so I spent my time reading.
“And then I started to worry because I would arrive at training without having closed my eys during the night.
“The doctor reassured me and prescribed me a medicine to help me sleep. Little by title, I managed to get some sleep.”
The trauma was understandable as Barca became the first team ever to overturn a four-goal deficit from the first-leg.
Psychologically there is an argument to say that the reigning French champions still haven’t recovered from that loss.
In the four years before the Barca encounter, PSG had reached four consecutive quarter-finals of Europe’s premier club competitions.
Since then, however, they have bowed out at the last-16 stage, most recently losing 3-1 to Manchester United in injury time despite having won 2-0 at Old Trafford.
Uruguayan Cavani has been in Paris since the summer of 2013 and has scored 134 goals for the club, including 23 in the 2018-19 season.
He has won 14 domestic trophies with the Parisians, including five league titles.
He has formed a menacing partnership with Neymar and Kylian Mbappe, though with speculation surrounding the future of those two, how long the fearsome trio will remain a pact is unknown.