Jansen underwent a successful three-hour ablation surgery performed by Dr. Koonwalee Nademanee at White Memorial Hospital on Oct. 23. During the procedure, the abnormal tissue in his heart was identified and then cauterized to stop the erratic electrical signals sent from the area.
Jansen said his heart went into an irregular beat when the surgery started, helping doctors quickly pinpoint the areas needing attention. He said he still has some stiffness in his groin area, where two small incisions were made, but otherwise feels better than he had.
"It wasn't scary at all," said the 25-year-old. "I just wanted to get it over with. I feel it's a relief and it will be good for me for the rest of my life. I just wanted to get it done, and I know this doctor is one of the great experts and I have a lot of confidence in him."
Jansen has had episodes the past two seasons that have required blood-thinner medication, which resulted in disabled list stints.
"The second time didn't scare me as much as let me know that there was a problem, and we needed to get it fixed," he said. "The first time, that was scary. This time, I just wanted to get on with it."
This year's episode occurred late in the season and resulted in newly acquired Brandon League assuming Jansen's closer duties.
The Dodgers are negotiating a three-year contract to keep League, who is eligible for free agency, but the club still believes in Jansen's ability to be a dominant late-inning reliever. He had a 2.35 ERA in 65 innings over 65 appearances this year with 25 saves (seven blown saves) and 99 strikeouts, taking the closer's role from Javy Guerra.
Jansen will be on blood thinners for three months and must avoid anything that could result in a cut or bruise. But he will be able to participate in controlled workouts and throw regularly off a mound. He said he expects to be "full strength and good to go" for the start of Spring Training.
When next year starts, Jansen believes he will be better than ever, not only because of the improvement in his health, but in the improvement of his velocity.
The former catcher has piled up strikeouts at a staggering clip, but for most of the 2012 season he did so despite a drop in velocity of his cut fastball. However, he accidentally discovered a mechanical flaw while playing catch in Washington after the Dodgers' Sept. 18 game was rained out.
"I was just playing around with the two-seamer and saw some great late movement," Jansen said. "I took it into a game against Colorado. I threw a 90-mph cutter, then A.J. [Ellis, catcher] asked me for a two-seamer and I hit 95. That's when I realized that I was staying behind the two-seamer but wasn't staying fully behind the cutter.
"From that point, my cutter got to 96 and touched 97. It's just a learning experience. I haven't been pitching that long. I have great pitching coaches in Rick Honeycutt and Kenny Howell, but you also have to be your own pitching coach and figure out how to do what they're telling you to do."