Philbin, 75, returned to his syndicated daytime talk show Thursday. The audience gave him a standing ovation as he walked onto the set with co-host Kelly Ripa.
"Finally back after six weeks. ... Yes, it was six weeks — and one day," said Philbin, spry and energetic as ever.
But in a press conference, Philbin said he continues to feel post-surgery pain.
"My chest hurts," he told reporters. "People keep telling me, `Hey, you look great.' I don't feel that great but I'm happy to be here."
Why is he back at work?
"Well, because it was time," he said. "It really was. And sometimes you delude yourself into thinking — you know, you get sort of a wave of hypochondria saying, `Maybe I shouldn't go back, this hurts, that hurts.' Yeah, it hurts but it's not enough to keep me away from the show."
Philbin said he loved having more time with his wife, Joy, but felt pulled back to the "Live" studio — his "home for many, many years now."
"Frankly, I don't know what I would do without this morning show," he said. "It's a wonderful show. It's exactly what I devised for myself selfishly back in 1961. ... But now it's a part of my life."
David Letterman, host of CBS' "Late Show," was Philbin's first guest on Thursday's program. Philbin was a guest host when Letterman underwent heart bypass surgery in 2000 and recovered from an eye infection in 2003.
Letterman quipped, "Look, Regis, don't be a hero if you need to lie down. Kelly and I can finish up here. This is a couple of heart patients, this isn't a TV show, this is a recovery room!"
Philbin and Letterman even lifted their pants to show scars on their legs from their bypasses, noted CBS News correspondent Bianca Solorzano on The Early Show Friday. Each had an artery removed from his leg to be used as a new cardiac blood vessel.
Philbin and Letterman also shared the same heart surgeons. The doctors and their medical team appeared as guests on the big welcome back show.
Ehile chatting with Ripa, Philbin mentioned he'd lost 8 pounds.
"I was unprepared for it. I didn't know what a bypass really was until I went through it, and then I found out it is a tough procedure."
The rewards are great, he said of the heart surgery, "But, in the meantime, that whole thing is a tough one."