PATIENT EDUCATION

The Next Generation
of Heart Tracking

Monitoring the rhythm of
your heart and alerting
you to changes

Smartphones are innovating how we diagnose irregular heartbeats. According to their press release this week, the results of the Apple Heart Study, Stanford Medicine verified that the Apple Watch can detect and report an “irregular heart rhythm (that) appears to be suggestive of atrial fibrillation (AFib).” AFib is quite common in the United States with more than 200,000 cases reported every year. At least 2.7 million Americans are living with AFib. People with untreated atrial fibrillation may be at greater risk for stroke than people with normal heart rhythms. Because blood does not flow through the atria regularly, blood clots may form in the heart. If a blood clot escapes from the heart, it can travel through the bloodstream to the brain and cause a stroke.

Your heart’s rhythm

Dr. James O’Brien is board-certified in clinical cardiac electrophysiology. An electrocardiogram (ECG, EKG) is a test that allows your doctor to see how well your heart is working. Dr. O’Brien describes his specialty as to an electrician, a specialist who investigates the wiring of the heart. “That’s where the heart is amazing. Our hearts are kind of like nerves, in the sense that they are electrically active; some of the nerves contract and that’s more muscular, some of them don’t, they conduct electricity. There’s an area called the sinus node that spontaneously fires and it’s kept in check by nerves. As we start to exercise or are active, our heart rates pick up. That area, the sinus node, is responsible for that change. The rest of the heart is inert. It sits there and waits for that sinus node to tell it what to do.”

Graphic of Heartbeat

When the heart beats, arteries expand as they fill with blood. When the heart relaxes, the arteries contract. It’s this rhythm between the heart and the arteries that powers your circulation system and keeps your blood flowing.

Dr. O’ Brien continued to explain the function of a heartbeat. “Some of the areas of the heart misbehave by themselves, and they try to run the show; those are atopic areas. People have, the term is PVC’s or premature ventricular beats, the most common reason for extra beats or skipped beats that leads for people to come in and say, ‘I feel palpitations or a sensation that my heart is beating abnormally.’ Many of those are due to PVC’s in an area of the lower chamber of the heart that depolarizes or fires by itself, competing with that normal rhythm. Many times when we sit down our heart rate slows down, and that area gets to discharge. If we get up to run the sinus rate is a little quicker, quieting down the PVC. This is why people say, ‘I don’t get them while I’m up and around, but I feel it more when I’m sitting.’ Some arrhythmias (abnormal heartbeat rhythms) are reentrant; those are different if you’ve had a heart attack or scare on your heart. As opposed to firing from a focus it re-enters, where the signal is spinning around, going from the healthy tissue, slowly through the scare and around again. That’s a reentrant arrhythmia, and those are much more serious.”

Before technology made it possible to see heart rhythms on a screen, doctors read EKG paper tapes. “We used to call them the squiggles,” he recalled. He explained the importance of understanding the difference between your heart rate and your heart’s rhythm. “When people say, ‘My heart rate was 72,’ well that’s good to know, it’s a significant number, 60 to 100 is normal at rest. But, what is the rhythm? Is it a regular rhythm? A top-bottom rhythm? Or is there atrial fibrillation, where the upper chamber is quivering, and the heart is not squeezing at all? This is when clots can form, and the electricity is being conducted to the bottom, you may have a heart rate of 72, and you may have AFib or an irregular rhythm. The rhythm of your heartbeat is what we are looking at on an EKG.”

Remote heart rate monitoring

It’s worth noting that the 2017 Apple Heart Study used older Apple Watch versions, not the Series 4 Watch that was unveiled this past fall, which has a built-in electrocardiogram (ECG) on top of the standard pulse sensor. Also, remote heart rate monitoring isn’t new technology. Dr. O’Brien pointed out that similar products have been on the market for the past 15 years. “AliveCore (the company who makes Kardia products) uses single lead EKG systems to detect the heart rate and the rhythm: regular, normal sinus or irregular, AFib.” The KardiaBand offers a replacement band for Apple Watches where users can conduct an “EKG anytime, anywhere” by placing their thumb on the band strap sensor for “a medical-grade EKG in just 30 seconds.” KardiaMobile pairs with most smartphones & tablets and uses a wireless strip sensor where users place their index and middle finger for “a medical-grade EKG in 30 seconds anywhere, anytime.” As Dr. O’Brien notes, these devices “create a PDF report on your phone which patients can send to us for review at the office.”

In September of 2018, Apple introduced the Apple Watch Series 4. This was the first smartwatch that can monitor your heart, and if it detects an irregular heart rhythm, notify you and record the episode. It instantly became the “hot-holiday” gift for heart patients. Apple continued its heart monitoring research with an announcement in January of this year that it had partnered with Johnson & Johnson to develop an app that can accelerate the diagnosis of a leading cause of stroke. Their study will start later this year, focused on US adults over 65 who wear the Apple Watch Series 4. “My strong suspicion is the study will be positive. For a device to give us information from an all-day sample is very helpful” stated Dr. O’Brien.

In a statement, Paul Stoffels, Johnson & Johnson’s executive vice president and chief scientific officer, said: “the goal is to identify early on AFib and prevent stroke by combining the physical know-how from Apple.” Both companies believe that the future of heart detection and treatment will involve cloud based technology, using virtual storage spaces that allow users to safely share their information with a click of a button. The Capital Cardiology Associates Patient Portal is a secure portal that allows you, as a patient, access to medical records including medications, lab results, and medical history — online. If you are interested in signing up for the Patient Portal, click here to download the policy form to print out and return at your next visit.

The role of wearable trackers in your health monitoring

There is a difference in the quality of the EKG on an Apple Watch, KardiaBand, Fitbit, or any other wearable tracker versus the diagnostic ability of a 12-lead EKG. Dr. O’Brien summed up the difference as “a single lead EKG is a screening test. It’s appropriate for monitoring and detecting rhythm states. A 12-lead gives us a more accurate picture for problems and locating their origins, but that doesn’t diminish the value of a single lead EKG.”

While the device manufacturers continue to test their products for accuracy, innovate with more sharing and reporting advancements, and the size of the device gets smaller with every new release, medical professionals generally support wearable trackers in monitoring your health and daily life. “For a device to give us information from an all-day sample is very helpful,” said Dr. O’Brien. “Patients will have more ownership of their heart health, making them active participants. The watch may say they are irregular. After an exam, we’ll see they are single isolated beats, completely benign, but that’s fine. We’ll be able to say, ‘look you’re okay!’ We’ll also have patients who we haven’t seen before coming to the office who say, ‘my watch says I have abnormal beats.’ We can look and find that their blood pressure is at 150 and that will bring up a whole different preventative issue of high blood pressure.”

Written by: Michael Arce, Capital Cardiology Associates
Any medical information published on this website is not intended as a substitute for informed medical advice, and you should not take any action before consulting with a healthcare professional.