Leadless Pacemaker: Game Changer for Mountain Biker

DeSpain faced health challenges in the past, but this was something entirely different. Periodically, and seemingly unprompted, the 52-year-old’s heart rate would fall to as low as 30 beats per minute (BPM), causing her to get lightheaded and fatigued. The typical BPM for an active adult is between 60 and 100. 

“All of a sudden, my heart rate started dropping into the low 30s. I would be just fine one minute, and the next I’m lying on the floor,” she says.  

She was taken to the hospital where an electrocardiogram (EKG) indicated symptomatic sick sinus syndrome and sinus bradycardia.  

Sick sinus syndrome is a heart rhythm disorder (arrhythmia) that affects the heart’s natural pacemaker, the sinus node, which controls the heartbeat.  

Sinus bradycardia is similar but reduces the rate of electrical discharge from the sinus node, resulting in a lower-than-normal heart rate. Both conditions can cause fainting or near-fainting, fatigue, dizziness, shortness of breath and chest pain.  

Sick sinus syndrome and sinus bradycardias are relatively rare among the general population and are more common in endurance athletes like DeSpain, who competes in six- to 12-hour-long races.  

She was coming to terms with her diagnosis when she heard the news that no one, let alone a masters-level athlete, wants to hear: You’re going to need a pacemaker.  

“I was like, no, no, no, you’re clearly mistaken. There’s just no way,” she recalls. “I’m young and healthy. My cholesterol’s fabulous. I’ve never smoked. I don’t drink. I don’t eat red meat. I do all the right stuff. Right?”  

A friend who had worked as a cardiac nurse recommended DeSpain see Nicholas Olson, MD, a cardiac electrophysiologist at Scripps Clinic Anderson Medical Pavilion in La Jolla.  

Electrophysiology is a cardiology subspecialty that focuses on the heart’s electrical activity and the treatment of arrhythmias. Cardiac electrophysiologists undergo more than a decade of medical training, which includes a three-year fellowship in cardiovascular disease and a two-year fellowship in clinical cardiac electrophysiology.  

“Decades ago, cardiologists did a little bit of everything. They’d deal with artery problems, electrical problems and whatever else came through the door,” explains Dr. Olson. “But as any specialty grows, it becomes more specialized. In loose terms, we now typically have general cardiologists who do diagnostics, then we have ‘plumbers,’ the stent doctors who fix the arteries and then we have ‘electricians,’ like myself, and we deal with the electrical parts of the heart.”  

Every year, Scripps’ board-certified cardiac electrophysiologists diagnose and successfully treat thousands of patients with arrhythmias.  

Working together with primary care physicians, general cardiologists and medical colleagues across multiple specialties and subspecialties, electrophysiologists provide the best possible treatment options for all types of arrhythmias. Scripps is a nationally and internationally recognized heart care leader and is consistently ranked by U.S. News & World Report as one of America’s Best Hospitals for cardiology and heart surgery. 

When DeSpain first met Dr. Olson, she noticed that he kept a book on lifestyle changes for longevity in an exam room. It’s a philosophy she also subscribes to, so she immediately knew she was in good hands.  

But DeSpain was still hesitant about the pacemaker. One of her main concerns was that the battery would interfere with her cycling, as the strap for the hydration pack that she used during endurance races would go right over the top of the device. She mentioned hearing from other pacemaker patients that even wearing a seatbelt comfortably could be difficult.  

Dr. Olson quickly alleviated her fears and put her mind at ease.  

“He said, ‘I think you could benefit from the pacemaker,’ and I immediately go into my ‘Listen, I don’t need it, I really don’t want to do this.’ He was so understanding. He took so much time to talk to me about what that meant,” DeSpain says. “He explained that there was this new leadless pacemaker, and that I’d be a good candidate for it, and it wouldn’t keep me from cycling.”  

After another incident when her heart rate dropped while she was out walking her dogs, DeSpain was fully on board.  

Due to DeSpain’s age, active lifestyle and condition, Dr. Olson opted to use new leadless pacemaker technology. The device was just approved by the FDA last year and DeSpain was the first Scripps patient to undergo the procedure.  

“One of the advantages of going to Scripps is that doctors who have become experts in these subspecialties have access to the newest techniques and technology, whether that’s in the context of a clinical trial, or access to advanced technology as soon as it becomes commercially available,” says Dr. Olson. 

 A leadless pacemaker is implanted into the heart’s right atrium or right ventricle through a very small incision in the femoral vein in the leg. The device itself is about 90% smaller than a traditional pacemaker — just three to four centimeters long. Since the entire device (which contains its power source) fits within the heart, leads, or wires that travel through the heart, aren’t needed.  

Unlike traditional pacemakers, leadless pacemakers do not require a separate battery to be implanted under the skin, and once inserted, the device is programmed to send small electrical impulses to the heart muscle as needed.  

Not having to place leads in the heart helps avoid blockages and degradation that can occur over time, which can happen faster in people like DeSpain who are particularly active. There’s also no visible scarring, no pacemaker bulge on the chest and no restrictions to arm movements.  

The lifespan of a leadless pacemaker is similar to that of a traditional pacemaker, roughly eight to 12 years. Once its generator runs its course, it can be turned off and a new device implanted.  

“Pacemakers have gone through an evolution of development. The first pacemaker was external. It was on a cart that the patient had to wheel around — and had wires that went from the cart into the patient’s heart. From there, devices kept getting smaller and smaller,” says Dr. Olson.  

“Traditional pacemakers have long wires that go all the way down into your heart, and bend back and forth with every single heartbeat, which can create problems over time,” he continues. “The concept of a mini pacemaker with no wires, or anything underneath the skin, eliminates all of those potential complications.”  

DeSpain had the leadless pacemaker implanted in her heart’s right atrium on June 19, 2024.  

“If she had come by six months earlier, we wouldn’t have had this as a possibility for her,” says Dr. Olson.  

DeSpain’s surgery went off without a hitch. The surgery itself took just 20 minutes, and the difference she felt after the procedure was night and day.  

Dr. Olson recalls DeSpain’s initial reaction.  

“The next morning when I walked into her room, she had this wide-eyed expression and said she already felt amazing,” he says. “She’d been reluctant and considered a pacemaker a last resort. So, the realization that a lot of these symptoms were going to be gone was really overwhelming for her.” 

DeSpain was feeling back to normal within a week, and in three weeks was back on her bike, riding 100-plus miles each week and doing interval training. In November, she was racing again and has a full schedule planned for 2025.  

“It’s fantastic. It’s like there’s nothing wrong with my heart anymore,” she says. “Dr. Olson gave me everything back. It’s not just being able to ride my bike and race, but he also gave me back being able to walk my dog, being able to go on a hike with my daughter, being able to just do little things by myself without being afraid I’m going to pass out.”  

DeSpain is still in awe that something so tiny could have such a big impact.  

“I feel normal. I mountain bike and gravel bike with people who are younger than me, and I’m doing just fine. You’d never know,” she says. “This tiny little thing has made a profound difference in what I’m able to do, and how I feel. It’s just amazing.”