Cheney told "Fox News Sunday," "I was in in-stage heart failure" before the pump was implanted last summer.
"I've been blessed with the wonders of modern medical technology," he said. "And I'm getting ready to go fishing at the end of this month and working on a book and spending a lot of time with family."
With an electronic device permanently attached, "you're not supposed to fall in" the water, he said, or swim.
Asked about a possible heart transplant, Cheney said: "I haven't decided yet. I'm not prepared to make any medical announcements today."