The 33-year-old shared the news on Facebook, saying that he does not have cancer, despite previous reports claiming so.
Sleggs plays the character Slugs on This Country, the BAFTA-winning comedy created by Charlie Cooper and Daisy May Cooper.
“Recently I was put onto palliative care [because] my heart failure was getting out of control,” the actor wrote on Facebook.
“By last Friday I was certain I wouldn’t be here the next week but miraculously I made some sort of great turn around over the weekend.
“I don’t know how long this turn around will last but I’ll try and keep alive as long as I can.”
Sleggs previously wrote on social media that his health had been deteriorating ”fairly rapid’.
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