A clinical atrial fibrillation trial heralds the wireless future of personalised medicine.
By Kira Peikoff
Millions suffer from atrial fibrillation, a quivering heartbeat that can lead to blood clots and increase the risk of a stroke by 500 per cent. The condition is currently treated with a lifetime course of continuous blood thinners, which are effective at preventing blood clots, but raise the chances of serious bleeding.
Dr Rod Passman, a cardiology professor at Northwestern University in the USA, recently conducted a study with a radically different approach: cardiac monitors the size of a paper clip were inserted under the skin to measure the electrical output of patients’ hearts in real time.
The monitors alerted Dr Passman with a text message if they detected signs of A-fib. When that happened, he’d initiate a course of next-generation blood thinners that would act just long enough to normalise patient’s rhythms. Without inventing a new device or discovering a new drug, Dr Passman’s novel integration of the two into an on-demand system stands to transform the way we treat the sick.
Real-Time Cardiac Care
1. The cardiac monitor tracks heart signals.
2. A second device uploads the data via cell network.
3. Patient condition reports are available online.
4. If A-fib is detected, the doctor gets a notification.
5. The patient is given fast-acting blood thinners until the heart is back to normal.
Speaking with Dr Passman
Popular Mechanics: So how does this device work?
Rod Passman: Your heart sends out electrical signals, and they can be recorded from anywhere in the body. This implantable cardiac monitor, so small it’s actually injected underneath the skin with a special tool, reads the electrical activity and feeds it to a website. When you develop A-fib, the heart rate becomes very erratic. The device sees the irregularity and via the website alerts me with a text.
PM: What led to this new approach?
RP: One piece of the puzzle was the development of drugs that could rapidly thin the blood, and the other piece was that we had to have technology that could provide long-term cardiac monitoring with remote transmission. If we were able to monitor you and let you know quickly, we could potentially thin your blood early and prevent a blood clot from forming, providing the benefits of a blood thinner, with minimal risks.
PM: What did the study show?
RP: In a small group of 59 patients, we reduced time on the blood thinner by 94 per cent. But to show that this is safe, we need a very large study, so we’re planning a 6 000-patient trial.
PM: Has this remote monitoring approach been used before to guide clinical decisions?
RP: My study is the first example of using these devices for patient management rather than diagnosis. The device and drug are already out there, but we’re using them in a way they weren’t intended to be used. I would say I didn’t invent chocolate, I didn’t invent peanut butter, but I invented Reese’s Peanut Butter Cups.
PM: My favorite candy. As wireless technology improves, what’s next?
RP: The device will communicate directly with a patient’s phone. My vision is, just like a diabetic checks their blood sugar and treats themselves, in the future the patient with atrial fibrillation might take blood thinners on their own in response to data from this chip inside their body.
Ultimately, these devices will not just see the rhythm of the heart. Maybe they could see things like blood pressure or glucose levels. Tell you whether you’ve been mobile or not. The potential usefulness of these devices is really quite remarkable.
PM: One day, will we all end up wearing one to monitor us before something goes wrong? Is this basically a Fitbit on steroids?
RP: (laughing) A Fitbit is a toy compared with this. One can envisage it as a long-term health-management tool. The concept of waiting until you’ve fallen off the cliff to come to the doctor or to recognise a disease after it’s got out of control could be obsolete. Think of the efficiency, we could monitor thousands of patients from their homes. We see problems before the patients see problems.
PM: Sounds like a new paradigm that’s still far away.
RP: It’s a lot closer now than ever.