DeRosa flew to Chicago on Monday and will be examined by cardiologists and some of the Cubs' medical staff there on Tuesday in an attempt to find a solution.
"I've always been able to control it with breathing exercises," said DeRosa, who was hospitalized on Saturday night at a Mesa hospital after experiencing an irregular heartbeat during a spring workout.
"I went through a gamut of tests when I was in high school to make sure it was nothing serious," he said. "It's never been a problem. I've been able to have certain techniques over the years that have got me out of the situation. It's never been an issue.
"The other day, it didn't get progressively worse but just lasted a lot longer," DeRosa said. "I needed some help to get me back to the right heartbeat. That's why the precautions were taken to go over to the hospital."
DeRosa was first diagnosed with an irregular heartbeat when he was 16 years old, and the second baseman, who turns 33 on Tuesday, said it occurs once or twice a month.
"Some will last 10 seconds, some will last five minutes," he said. "This one happened to last a lot longer than that. It was one of those things where you start to get uncomfortable. At no time did I think I was going to lose consciousness.
"I wasn't dizzy," he said. "I wasn't feeling nauseous. It wasn't any of that. My heart was beating irregularly, and I couldn't get my techniques to get me back to normal."
The incident occurred during the fundamental drills at Fitch Park.
"I feel it instantly when it happens," DeRosa said. "It's something that -- sudden movement, whatever it may be, boom, I feel my heart go into a flutter. I control it and bring myself right out of it. I felt it during the rundowns and kind of just grinded it out and waited for it to go away, but it continued and it kept continuing. Then it's, 'Hey, maybe I should say something.' I went up to the trainer, to Mark O'Neal, and said, 'Hey, I'd like to get this looked at.'
"It's not something I'm super concerned with, but if I never have to deal with it again, I'd like to do that."
DeRosa said one option he's been told of is an outpatient procedure. Until DeRosa sees the cardiologist in Chicago, it was too early for the Cubs to speculate on what procedure, if any, that would be, a team spokesman said. DeRosa also could be put on medication, but would prefer not to go that route.
"I'm 32 years old, I don't want to be on medication the rest of my life," DeRosa said. "We'll discuss all those options. It's something I've been able to control without any help. The other day it was probably a wake-up call, and I probably need to figure some things out and get it fixed."
DeRosa isn't the first person to experience an irregular heartbeat, or atrial dysrhythmia.
"It's common, a lot of people in the world have it," he said. "It's one of those things that not a lot of people [with this condition] play Major League Baseball. It's something I, personally, am tired of dealing with. If there's medicine or a little procedure I can do to forget about it, I'd like to do that. I have noticed over the 15, 16 years that I've been diagnosed with it that I've been getting it a little more regularly as an adult and it's something I don't want to deal with anymore."
DeRosa didn't expect this to keep him sidelined for long, and hoped to be back on the field by the end of the week -- if the doctors let him.
"It's an issue, but it's not a big deal," he said. "It's something that will be quick, done and I'll be back on the field."
Was he ever scared on Saturday? His teammates were.
"I don't think I was scared," DeRosa said. "The looks on everyones' faces make you nervous. When the paramedics are called -- I tried to talk my way out of that. My hat goes off to [Dr. Stephen Adams] and our trainers and [athletic trainer] Mark O'Neal. Those guys are phenomenal. Would I have liked to have driven undercover to the hospital by myself? Yeah. I understand the ramifications if [I drove himself and] something were to go wrong. We did everything right.
"It's not something that will [keep] me from playing, it's not something I'm concerned about," he said. "It's something I want to fix and alleviate. If I don't have to deal with it, I'd like to not have to."
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.