Rev Giles Fraser announced he would not be working again for some time and praised the medical staff who had looked after him.
Writing on Twitter, the Church of England priest and Guardian newspaper writer said: "Thank you for all well wishes. I had a heart attack on Sunday and gonna be off for a while enjoying the hospitality of the wonderful NHS.
"Thank you for that kindness, twitter. You have made me cry."
Messages of supporting came from figures including Daily Telegraph writer Tim Stanley who said "Oh no! I had no idea. I'll pray for you. Get well soon." and author Dr Mark Stibbe: "Praying for you Giles and sending lots of love x".
The Dr who just saw me has been on A&E shift for 48 hours, including treating last night's victims. And he's still here. Thank you NHS.
— Giles Fraser (@giles_fraser) June 4, 2017
Rev Fraser said on Twitter "thank you" to the doctor attending to him in accident and emergency - who had also been responding to people caught up in the terrorist attack to hit London Bridge and Borough Market on Saturday night.
He also thanked a hospital chaplain who delivered a cross and a prayer, which read: "The Lord lift up his countenance upon you and grant you his gift of healing and peace."
The lovely Chaplain has been to give me a cross as say a little prayer with me. Thank you. pic.twitter.com/gNGs7Zt39L
— Giles Fraser (@giles_fraser) June 4, 2017
Last October, the priest resigned from his post of Canon Chancellor at St Paul's Cathedral, expressing his opposition to any move by the London landmark to forcibly evict anti-capitalist protestors encamped outside.