iRhythm is changing the game in a heart rhythm monitoring space that has been dominated for years by the Holter Monitor. Here’s how.
About 14 years ago, when Mark Day was interviewing at iRhythm, he could see the unmet needs that a project out of Stanford’s Biodesign program addressed.
While that was a start, there was still a way to go for what would become a massive disruptor in electrocardiograph monitoring and AFib detection.
“While the design and idea was very compelling — and even 14 years later we’re doing very much what that idea was and have brought it to life and are changing the standard of care as a result — the reality was that it was a hockey puck that never would have adhered very long to the chest. It was very much a concept,” Day, who is now iRhythm’s EVP of R&D, told Medical Design & Outsourcing. “Our challenge as medical device professionals was to figure out how to take this concept that was a great idea but was not obviously directly useful and have it iterated into something that could be impactful.”
By 2010, the company launched the first generation of its Zio platform for cardiac monitoring. While Day said it was effective, it remained that it was “very much” a first-generation offering with plenty of room to grow. These days, iRhythm is challenging the traditional Holder monitor with its next-gen Zio XT with a new and improved design of its flagship wearable Zio monitor and updated artificial intelligence (AI) capabilities. FDA cleared the changes in May.
The idea behind the Zio XT is increased adherence and better patient comfort. The patient shouldn’t even know they’re wearing the miniaturized device, including during events like exercise, showering and sleeping, according to Day. On top of the size and weight — approximately 50% lighter than the previous iteration — the device includes a breathable, waterproof outer layer and a “stay-put” adhesive with a flexible design for secure attachment on the left side of the chest.
A traditional Holter monitor can stay on a person for up to seven days, but it requires battery changing, electrode and wire removal and more. Day thinks the Zio XT offers something much more comfortable.
“We’ve created a very patient-compliant form factor that can be worn continuously, and that’s the goal,” Day said. “The patient doesn’t need to interact with the device over the 14 days. They don’t need to recharge it, change batteries or otherwise. That is what the result of patient compliance is. For Holter monitors, it’s very much more a burden on the patient.”
Zio XT yields 98% analyzable data over the two-week wear time, which Day says works out to approximately 1.5 million heartbeats for most patients. The next step — although it “doesn’t sound very digital health,” according to Day — is to mail the device back to iRhythm, where the company will analyze the data.
The recording amounts to about half of one gigabyte of data. The burden of transferring that data is not something the company wants to put on its customers, with a median age of 65 in the patient demographic. Day said the simplest thing, which demonstrates a “remarkably high” compliance, is putting the device in the mailbox.
Holter monitors are delivered back to providers and cleaned before being passed on to the next patient. In contrast, the Zio XT’s patient-facing components are discarded, and the printed circuit board is reused.
“Because [Holter monitors] are like capital assets that get lost, broken and are fairly expensive to replace — and we’ve done clinical studies on this — we’ve seen backlogs of up to months for patients waiting to get on what is essentially an asset,” Day said. “What we’ve created is more of a single-use diagnostic service where we stock the Zio XT product in the account more as a consignment type of model, and they just use it as they need it. That’s resulted in a pretty tremendous improvement in terms of the acknowledgment of the prescription or otherwise to the actual delivery of the report.”
Day said the Holter monitor does hold the advantage over Zio XT in that it offers wider wire placement with more vectors to help with monitoring. However, the iRhythm executive likened the head-to-head between the platforms to a football game in which you can opt for three camera views for one quarter (Holter) or one camera for the entire game (Zio XT).
The company sees that, even in patients whose frequent symptoms might find a Holter more valuable in providing diagnostics, the two-week wear time gives a “much more diagnostically capable view” of what’s going on with a patient’s heart rhythm. Day said that Zio often doesn’t just find one arrhythmia causing the symptom but multiple arrhythmias interacting with that symptom, leading to different treatments.
“From the time it’s activated, either in the clinic or the home environment, [Zio] simply just records ECG,” Day said. “The Zio XT does not analyze in real-time; it just focuses on making sure we create a diagnostically complete and accurate recording of what happens over the patient’s electrophysiology experience over two weeks. In that, we’ve created a diagnostic service that really meets this unmet need.”