STILL ATHLETES AT HEART
Some cardiac-device recipients don't want to give up sports, so a medical registry tracks how they're doing.
BY CHRISTOPHER SNOWBECK PIONEER PRESS
For heart patients who have defibrillators implanted in their chests, the conventional wisdom when it comes to competitive sports is simple: Stick to golf. Or bowling.
Doctors worry that rigorous athletic activity could stress a patient's heart and prompt either an appropriate or inappropriate shock from the defibrillator, which is designed to detect and correct potentially fatal heart-rhythm problems. Another concern is that the defibrillator's life-saving jolt might not be effective when an athlete is at the peak of exercise.
But as implantable cardiac defibrillator (ICD) technology has spread to more patients, a small but growing number of heart-device recipients are forging ahead with competitive running, skiing and other sports. These ICD athletes are being counseled by physicians who understand the conventional wisdom, but also know that the broad recommendations are backed by few studies and must be tailored for individual patients.
A new patient registry being funded by the country's big three heart-device companies - all of which have major operations in the Twin Cities - will track up to 800 ICD athletes in hopes of better defining when it's safe to compete.
"What we're talking about is patients who want to continue to participate in organized sports," said Dr. Mark D. Carlson, chief medical officer in the cardiac-rhythm-management division of Little Canada-based St. Jude Medical.
"We don't have a lot of evidence for how safe this may or may not be in certain patients, so our guidelines tend to be very conservative," Carlson said. "It may be that for some patients it's very appropriate for them to participate in certain organized sports activities."
The research project, called the ICD Sports Registry, is being funded by St. Jude Medical, Fridley-based Medtronic and Natick, Mass.-based Boston Scientific, which manufactures defibrillators in Arden Hills. The companies are the leaders in the $6 billion global market for implantable cardiac defibrillators, each of which costs about $30,000.
Annette Ruzicka, a spokeswoman for Boston Scientific, said the registry information won't help the companies sell more devices. But the study is an example of the kind of post-market research that manufacturers try to encourage, she said, because it helps explain the impact of devices on patients' quality of life.
Getting a shock is not a trivial matter.
When University of Washington basketball player Kayla Burt attempted a return to competitive sports after receiving an ICD, she abruptly quit after sustaining two shocks during a game.
"It felt like a bomb exploded in my body, pretty much," Burt said, according to a January 2006 article in the Seattle Times newspaper. "And not a small bomb - like an M-80 firecracker. I just hope I never feel that again."
The risk to the ICD athlete is compounded, doctors say, by the potential risk to other competitors. Think of a cyclist in the middle of a pack of racers being jolted off a bicycle due to the powerful shock delivered by the defibrillator.
That's why an expert panel assembled in 2005 recommended that ICDs should disqualify athletes from most competitive sports, with the exception of low-intensity events such as golf, billiards and bowling. Most contact sports were ruled out for pacemaker patients, as well, because bodily trauma could damage the device.
The panel acknowledged that the absolute risk of competition could not be determined with certainty for individual patients, and could be low in certain individuals. But members said they would err on the side of caution in their recommendations, even if that meant some athletes withdrew from competition unnecessarily.
The panel defined competitive athletes as those who participate in an organized team or individual sport that requires regular competition as a central component. These athletes place a high premium on excellence and achievement, and require systematic and usually strenuous training.
Dr. Barry J. Maron of the Minneapolis Heart Institute was a member of the panel. While Maron is a member of the steering committee for the new research registry for ICD athletes, he said he has questions about its goals.
"If it's about recreational physical activity with an ICD, sure, because we do advise our patients that they can live a normal life, so knowing what the limits of that appear to be would be useful," Maron said. "Where I'm not sure about it's purpose is with respect to competitive sports, because we have guidelines that basically recommend that most competitive sports are not compatible with defibrillators."
But this conventional wisdom apparently is out of step with what's actually happening.
A survey of 614 heart specialists published in 2006 found that only 10 percent said they recommended that defibrillator patients avoid all sports more vigorous than golf. What's more, 71 percent reported caring for patients who participated in sports, including vigorous competitive events such as basketball, running and skiing.
The results help explain the need for the ICD Sports Registry, said Dr. Rachel Lampert, a Yale University researcher and a leader of the research project. The registry does not endorse competitive sports for patients, Lampert noted, but seeks to track the experiences of ICD athletes to better inform future patients and their doctors about risks.
"From (the 2006) survey, we got the sense that a lot of patients are out there doing sports regardless of what we might or might not be telling them," she said. "And the risk might be less than we've postulated, although there were limitations to the survey."
Defibrillator manufacturers see a need for more information on the subject, too - particularly with the spread of implantable defibrillator technology.
Originally, doctors recommended defibrillators primarily for patients who had survived an episode of sudden cardiac arrest. Now, doctors also try to use defibrillators before patients have even one episode, said Dr. David Steinhaus, the medical director of Medtronic's heart rhythm device division. These "primary" prevention patients typically are younger, healthier and have fewer symptoms than "secondary" prevention patients.
As more devices are used in this preventive way, Steinhaus said, the sports question becomes more of an issue.
Erica Kindig, a 34-year-old runner in Orlando, Fla., is a prime example.
Kindig started running competitively three years ago and quickly became hooked on the stress relief it provided. She completed her first marathon in December 2005, and in her second race missed qualifying for the prestigious Boston Marathon by just 13 minutes.
But as Kindig's love for running was developing, she learned she suffered from a rare genetic disorder that puts her at risk for sudden cardiac arrest.
Kindig made a deal with her husband that she would get an implantable defibrillator as a sort of insurance policy against the condition. But the prospect of quitting running, when she had no symptoms, was too much, said Kindig, who is a cardiac nurse.
The experience has given Kindig insights into why patients aren't always compliant with physicians' orders.
"My doctor knows I compete, but isn't thrilled about it," said Kindig, who is one of the first 30 patients to join the ICD Sports Registry.
"The consensus statement from the doctors needs to be interpreted on a case-by-case basis," she said. "The decision is a personal one for the patient."