The American started the day two shots off the lead and was four back after Kieffer picked up six shots in seven holes to take control at Diamond Country Club.
But as Kieffer's momentum stalled in a two horse race, Catlin took his birdie tally for the day to seven as he carded a bogey free 65 to set the target at 14 under.
In the group behind, the German found sand off the 18th tee but showed nerves of steel to get up and down for par and the contest went to extra holes.
Both men had good chances as the first four trips back up the last were halved but Kieffer found the water three times at the fifth time of asking and Catlin took the crown with a bogey.
He could rise as high as a career best top 80 in the Official World Golf Ranking and with ten worldwide victories to his name already, the 30-year-old shows no signs of stopping there.
"I'd love to crack that top 50 in the world," he said. "Just get a chance to play in some Major Championships - I've actually never played in a Major. I'm thinking this gives me a very good chance to play in the US PGA Championship, that was kind of my goal.
"Hopefully it's good enough and to get into those events and to have the chance to win a Major, that's been my goal since I was a kid.
"Winning is never easy, it doesn't matter what tour you're playing on and to have gotten this one is definitely something special."
As overnight leaders Alejandro Cañizares and Kaymer quickly fell back, Kieffer two putted the par five first for a birdie, with Catlin holing a 15 footer from the fringe at the third to sit just one back.
Kieffer got a nice bounce at the third to hole from four feet but Catlin made a birdie at the par five next before Kieffer put his second to 12 feet and rolled in an eagle to lead by three.
Catlin made an 18 footer at the sixth to trim the gap once again before Kieffer holed from 15 feet at the fifth and, when the leader got another fortunate bounce to set up a four foot birdie at the seventh, he was four ahead.
California-native Catlin then put an approach to five feet at the eighth and with the group in third six shots back, it was firmly a two horse race.
Kieffer made a first bogey of the day on the ninth, with Catlin trimming the gap to one with a brilliant 25 foot putt on the 11th.
Another Kieffer bogey on the 11th meant we were tied and Catlin then made a 30 footer on the 14th to lead on his own for the first time.
Kieffer recovered from his stumble with an approach to ten feet on the 13th and he had the lead on his own once again as got up and down on the par five 15th to get back to 14 under.
Catlin then made an up-and-down of his own on the following par five to tie things up and the duo parred their way home to set up the play-off drama.
They had a birdie chance each on the first two play-off holes and Kieffer holed a 30 footer on the third to pile on the pressure but Catlin also made his birdie from a third of the distance.
A stunning bunker shot helped Catlin save par on the fourth trip up the 18th before Kieffer found water once from the tee and twice from the drop zone to make the result a formality despite Catlin finding sand again.
"It's always tough to watch that happen," Catlin added. "We're out here giving it our all, he's obviously a very, very accomplished player and to come out on top is something I will always cherish."
Kieffer said: "Standing here I feel like I’m only going to get better. Sometimes it doesn’t happen that way, you never know in golf, but I’m confident about the game and I felt good.
"Every shot on the play-off felt good too but the last shot was a bit stupid, I got a bit too aggressive."
Kaymer recovered brilliantly after dropping three shots in his opening three holes, with the two time Major Champion making six birdies to sign for a closing 70.
Besseling signed for a 67 with Armitage and Higgo recording rounds of 68 to finish a shot ahead of Spaniard Cañizares, Australia's Austin Bautista, Dane Nicolai Højgaard, South African Jacques Kruyswijk and local favourite Matthias Schwab.