As I pointed out Friday, Apple’s claim that the ECG sensor on their new Apple Watch 4 (available “later this year”) is “the First ECG product offered over the counter directly to consumers” is totally bogus.
AliveCor’s Kardia mobile ECG device was approved by the FDA for over the counter direct to consumer sales on February 10, 2014. Apple had to have known this as they worked with AliveCor to bring the first Apple Watch based ECG device to FDA approval in 2017.
I tried but failed to get AliveCor founder Dr. David Albert’s thoughts on Apple’s disinformation but Yahoo finance was able to speak to Vic Gundotra, the CEO of AliveCor:
Over at the headquarters of AliveCor, a startup based in Google’s hometown of Mountain View, they, too, were surprised by the announcement, CEO Vic Gundotra said in a phone interview on Thursday. Gundotra is a former Googler, widely known as the executive behind the Google+ social network.
Gundotra was also surprised by Apple’s claims of ECG primacy
“We were watching [the announcement], and we were surprised,” Gundotra said. “It was amazing, it was like us being on stage, with the thing we’ve been doing for 7 years,” referring to AliveCor’s product for detecting atrial fibrillation (AFib), a tough-to-spot heart disorder that manifests as an irregular, often quick heart rate that can cause poor circulation.
“Although when they said they were first to go over-the-counter, we were surprised,” he continued. “Apple doesn’t like to admit they copy anyone, even in the smallest things. Their own version of alternative facts.”
One man’s alternative fact is another (less polite) man’s lie.
Gundotra apparently views Apple’s entry as a good thing
“We love that Apple is validating AFib; just wait until you see what AliveCor is going to do next,” he said. “We were a great restaurant in a remote section of town, and someone just opened a giant restaurant right next to us, bringing a lot more attention.”
And as I pointed out previously, the AliveCor mobile ECG device (not the Kardia Band) is significantly cheaper than an Apple Watch and has multiple studies showing its accuracy. Interestingly, Gundotra indicates AliveCor sales has increased after the Apple announcement,.
“Ours is $99, theirs is $399, our sales popped yesterday, big time,”
On February 10, 2014 AliveCor, Inc. announced that its heavily validated personalmobile ECG monitor had received FDA over-the counter clearance. Previously the device, which allows recording of a single-lead ECG and, in conjunction with a free smart-phone app, can diagnose atrial fibrillation was only available by prescription.
Since 2013, I have been successfully using this device with my patients who have atrial fibrillation (and writing about it extensively)
I was shocked, therefore, to hear the COO of Apple, Jeff Williams, announce that Apple will be offering in its new Apple Watch 4 “the first ECG product offered over the counter directly to consumers.”
This seemed blatantly inaccurate as AliveCor’s device clearly preceded by 4 years Apple’s claim.
Furthermore, AliveCor’s Kardia Band which converts any Apple Watch into a single-lead ECG (which I’ve written about here and here) has been available and providing the Apple Watch-based ECGs since November 30, 2017.
AliveCor has an outstanding website which documents in detail all the research studies done on their products (there are dozens and dozens of linked papers) and all of their press releases dating back to 2012. It also explains in detail how the product works.
AliveCor shortly thereafter (December 12, 2017) announced Smart Rhythm , an Apple Watch app that monitors your rhythm and alerts you if it thinks you are in atrial fibrillation. I’ve discussed Smart Rhythm here.
The new Apple Watch’s rhythm monitoring app sounds a lot like Smart Rhythm but without any of the documentation AliveCor has provided.
So, within 10 months of Alivecor providing the world with the first ever wearable ECG (and proven its accuracy in afib) Apple seems to have come out with a remarkably similar product.
The major difference between Apple and AliveCor is the total lack of any reviewable data on the accuracy of the Apple device. Yes, that’s right Apple has provided no studies and no data and we have no idea how accurate its ECG device is (or its monitoring algorithm).
For all we know, it could diagnose sinus rhythm with frequent APCS or PVCs consistently as atrial fibrillation, sending thousands of Watch 4 wearers into a panic and overloading the health care system with meaningless alerts.
Apple’s website claims
Apple Watch Series 4 is capable of generating an ECG similar to a single-lead electrocardiogram. It’s a momentous achievement for a wearable device that can provide critical real-time data for doctors and peace of mind for you.
Apple’s “momentous achievement” was actually achieved 10 months earlier by AliveCor and if its monitoring algorithm and ECG system are significantly worse than the proven AliveCor system they will be destroying the peace of mind of users.
After describing the Apple Watch’s new health features, Jeff Williams introduced Ivor Benjamin, MD, the President of the American Heart Association. Benjamin proceeded to describe the new Apple Watch cardiac features as “game-changing”, noting that the AHA is committed to helping patients be “proactive.”
Does Benjamin have access to the accuracy of the Apple Watch ECG sensor? If so, he and the AHA should immediately share it with the scientific community. If not, by endorsing this feature of the Watch he should be ashamed. Users need to know if he or the AHA was paid any money for this appearance. Also, we should demand to know if (as the prominent AHA logo suggested and news reports implied) the AHA is somehow endorsing the Apple Watch.
Frequent readers know I’m a huge Apple fan but this Apple Watch business makes me think something is rotten in the state of Apple.
As I described here, the Kardia Band (KB) is an FDA-approved Apple Watch accessory available to the general public without a prescription which records a high quality single-lead ECG.
I’ve been using mine now for a while and can confirm the ease and accuracy of the ECG recordings it makes. I find recordings made with my Apple Watch/Kardia Band are reliably high quality with minimal artifact (unless I’m running on a treadmill.)
Once the 30 second recording is completed, the Kardia app on the Apple Watch takes about 5 seconds to process the information using an AI algorithm and then makes a determination of normal sinus rhythm (NSR), atrial fibrillation or unclassified.
In the JACC study, investigators from the Cleveland Clinic studied 100 consecutive patients presenting for cardioversion from AF with recordings made before and after the procedure. KB interpretations were compared to 12 lead ECGS read by electrophysiologists.
KB interpretations identified AF with 93% sensitivity and 84% specificity. Of the total 169 recordings, 34% were unclassified due to short recordings, low-amplitude p waves, and baseline artifacts.
The authors concluded that the KB algorithm for AF detection, when it is supported by a physician review can reliably differentiate AF from NSR.
(Of note the lead author on this study is on the advisory board of Alivecor the maker of the KB and AliveCor (AliveCor, Mountain View, CA) provided the Kardia Band monitors which were connected to an Apple Watch and paired via Bluetooth to a smartphone device for utilization in the study. AliveCor was not involved in the design, implementation, data analysis, or manuscript preparation of the study.)
My Updated Kardia Experience
I have found the standard Kardia device to be immensely helpful in the management of my afib patients before and after cardioversions (see my prior description here). The paper mentions that 8% of these pre-cardioversion patients showed up for the procedure in normal sinus rhythm, noting that
For each of these patients, the automated KB algorithm did not erroneously identify AF, and the physician interpretation of the KB recording correctly confirmed SR in each case.
Needless to say, it is better to find out a cardioversion is not needed before the patient shows up for the procedure. I would estimate this happens about 5-10% of the time in my practice.
The Kardia device or the KB is also really helpful post cardioversion. If the patient makes daily recordings (which I can review on Kardia Pro online) h/she and I know exactly how long sinus rhythm persisted before reverting back to AF.
This is important information which impacts future management decisions.
Kardia Band Versus Standard Kardia Device
None of my patients have purchased the Kardia Band most likely due to the cost and the fact that they don’t have an Apple Watch. If you have an Apple Watch and want to monitor your heart rhythm I think the KB is a good choice. Otherwise, the original AliveCor mobile ECG device continues to do a fantastic job (in conjunction with Kardia Pro, see here).
The combination of Kardia and Kardia Pro has substantially reduced my use of expensive and annoying long term monitors in my AF population.
In my next update on the KB I will share a reader’s real world description of the pros and cons of the KB (with Smart Rhythm monitoring) in a patient post cardioversion for AF.
Sometimes AliveCor’s Mobile ECG device yields unclassified interpretations of recordings. Understandably if you want to know whether your rhythm is normal or atrial fibrillation, the unclassified classification can be very frustrating.
There are various caues of an unclassified tracing with different solutions. Some unclassified recordings are due to a heart rate over 100 BPM or under 50 BPM and cannot be fixed. Similarly, some patients with ectopic beats like PVCS may consistently generate unclassified interpretations (see my discussion here).
Artifacts induced by poor recording techniques are common as a cause and almost always can be fixed.
These can be reduced by minimizing motion, extraneous noise, and maximizing contact with the electrodes. Follow all the steps AliveCor lists here.
For me, the following step is crucial
If your fingers are dry, try moistening them with antibacterial wipes or a bit of lotion
And be aware the device needs to be near the microphone of your iPad or smartphone.
Low Voltage As Cause of Unclassified Kardia Recordings
Another cause of unclassified interpretations is a low voltage recording (which I initially discussed here.).
At the recent ACC meeting I asked Alivecor inventor and CEO David Albert if he had any solutions to offer for those who obtain unclassified low voltage AliveCor tracings.
He told me that the cause is often a vertically oriented heart and that recording using the lead II technique can often solve the problem.
Lead II involves putting one electrode on your left knee and one your right fingers as described in this video:
Reader “J” recently sent me a series of Kardia ECG recordings, some of which were unclassified , some normal and one read as possible atrial fibrillation.
The unclassified and possible AF tracings looked like this:
They were very regular with a rate between 80 and 100 BPM but they totally lacked p waves. It was not clear to me what the rhythm was on these tracings.
Other tracings had lowish voltage but the p waves were clearly visible and Kardia easily classified them as normal
Still others had improved QRS voltage with clear p waves and were also classified appropriately as normal
After some back and forth emails we discovered that the ECG recordings with no p waves were always made using the chest lead recording. AliveCor-describes this as follows:
For an Anterior Precordial Lead, the device can be placed on the lower left side of the chest, just below the pectoral muscle. The bottom of the smartphone or tablet should be pointing towards the center of the body.
There is an abnormal cardiac rhythm that is regular between 80 and 100 BPM with no p waves and normal QRS called junctional tachycardia but in J’s case the absent p waves are related to the recording site.
Also, note that for this young woman the lead II voltage (Type B tracing) is much higher than the standard, lead I voltage (type A tracing).
Lead II With Pants On
After Dr. Albert told me of the advantages of Lead II I responded that it seemed somewhat awkward to take one’s pants off in order to make an ECG recording.
He immediately reached in his suit pocket and pulled out a pen-shaped device and began spraying a liquid on his left knee.
To my surprise he was able to make a perfect Lead II recording without taking his pants off!
Lessons learned from reader J and Dr. A:
Consider trying different leads if the standard Lead I (left hand, right hand) is consistently yielding unclassified ECG recordings
Try Lead II (left knee, right hand) to improve voltage and recording quality
You can record off your knee even with your pants on if you are prepared to spray liquids on your pants
The skeptical cardiologist recently received a package from American Medical ID, which loudly proclaimed that “Medical IDs Save lives!” The company suggested that I “Fully Open” my display and place it in a prominent location. I’m sure you’ve seen these types of displays in your doctor’s office:
I really don’t like promoting products in the office waiting room that haven’t been proven to be helpful, so I began wondering if medical IDs really do save lives.
American Medical is one of many for-profit medical ID jewelry makers who engrave various forms of jewelry with the medical information a patient gives them, with the hope that it will provide crucial information if the patient is unable to provide it themselves.
is a non-profit, charitable, and membership-based organization dedicated to the well being of others. Founded in 1956 by Dr. Marion and Chrissie Collins, the foundation’s mission is to protect and save lives by serving as the global information link between members and emergency responders during medical emergencies and other times of need. As a non-profit organization, MedicAlert Foundation is governed by a volunteer board of directors, comprised of highly respected national leaders from the healthcare profession and business.
MediAlert jewelry is supported by a 24/7 call center which claims to have access to the users medical records.
While communicating with first responders, MedicAlert will retrieve your MedicAlert health record and provide your health history – including medical conditions, medications/dosages, allergies, past surgical history. We will also provide your personal identification and emergency contact information to ensure you are quickly reunited with loved ones. If you are being transported to a facility, MedicAlert will also fax your health record so your information is available upon arrival
Medical ID Jewelry Accuracy
I am unaware of ever providing MedicAlert with medical information on any of my patients, so I assume the information that they have available is provided by the patient themselves, and may or may not be accurate and up to date.
Actually, one has to be concerned whether the patient information on any medical ID jewelry is up to date and accurate. If it’s not accurate, it could potentially confuse care providers and lead to more errors in care.
Given the potential downsides of medical ID jewelry, is there any evidence that it saves any lives, let alone millions?
There are, of course, anecdotes. And these dramatic stories help propel sales of millions of bracelets and necklaces.
Stylish Medical ID Jewelry
Lauren’s Hope is a Missouri company which a heart-warming story of its genesis: Lauren, a teenager with type I diabetes did not want to wear her medical ID bracelet because it wasn’t stylish. A new interchangeable bracelet was created.
Named after its inspiration, Lauren’s Hope quickly became a bustling kitchen-table business. In its first year, the company saw phenomenal success, particularly after the infinitely talented Halle Berry wore her Lauren’s Hope medical ID bracelet on the Rosie O’Donnell show when discussing her own Diabetes diagnosis. Practically overnight, people who had grudgingly worn, or even refused to wear, the standard, plain metal medical ID bracelets of the past suddenly had attractive, durable, stylish options they could enjoy wearing and change to suit their mood, outfit, or activity.
Today, more than 500,000 people wear Lauren’s Hope medical IDs every day, and we’re proud to say that number just keeps growing.
The compelling argument for a Type I diabetic to wear a Medical ID bracelet is that if they become confused or unresponsive from hypoglycemia, a paramedic or bystander can immediately recognize the situation, give glucose and save a life.
The problem with this seemingly apparent benefit is that the paramedic should not assume an unresponsive person who is a diabetic is hypoglycemic; other causes should be considered and evaluated. Likewise, hypoglycemia should be considered and tested for in an unresponsive person who is not known to be a diabetic.
(Before excoriating me for the above heresy, let me state that I am not advocating that insulin-dependent diabetics rip off their Medical ID bracelets)
What does Science Tell Us?
If you do a Google search asking the question “Do Medical ID’s Save Lives?” the vast majority of search results are various links to Medical ID company websites.
I was unable to find any scholarly article which addressed the question of lives saved by medical ID jewelry, but I found one 2017 British paper which questioned the benefits after a review of the scanty literature on the topic.
The paper begins with a table listing their suggestions for potentially appropriate and inappropriate inscriptions on alert tags:
From a cardiac standpoint, the relevant conditions are 1) the one medical implant they mention-an ICD (implantable cardiovert-defibrillator) 2) prosthetic heart valves, and 3) anticoagulants.
I have to say that in my 30 years of practicing cardiology I have never advised a patient with one of these conditions to wear a Medical Alert ID.
The same considerations I mentioned for the unresponsive diabetic applies to these cardiac conditions. For example, some patients with pacemakers or ICDs should not get MRIs. If an MRI is indicated on a patient that cannot give a history, it is the responsibility of the radiologists and technicians to make sure that the patient has not had an implant that would put them at risk. Thus, a careful search of the body for signs of surgery is warranted, with a standard Xray if an implant is suspected (see here).
The British paper authors conclude:
The striking result of our literature review is that there is an implicit assumption that medical IDs work, and themselves lead to minimal harm. Our commercial review revealed that these products are readily available for purchase from several companies, with no mandatory governance or minimum standards to ensure the accuracy or appropriateness of the information provided.
With regard to MedicAlert Foundation
The UK headquarters of MedicAlert Foundation has provided support for > 300,000 members (www.medicalert.org.uk/about-us/our-history); worldwide, this number rises to millions (www.medicalert.org/about/who-we-are/history). Membership with MedicAlert Foundation includes the checking of medical content displayed on the jewellery for appropriateness by a team of registered nurses (although it is unclear in which jurisdiction these nurses should be registered). The information provided to them is reliant on patient self‐reporting with no required input from the patient’s physician or access to their medical records.
They point out that “self-declaration” of patient illnesses and allergies may worsen outcomes:
. Bojah et al. describe an ‘allergy to anaesthesia’ inpatient wristband, that demonstrates how reliance on patient self‐reporting has the potential to cause dilemmas at a time when patients may be unable to elaborate 19. In an unregulated environment, mistakes or confusion of drug intolerances with allergies could mislead. For example, in the context of antimicrobial therapy, ~ 10% of the general population in the UK claim to have a penicillin allergy; however, only < 1% truly have an adverse immunological drug reaction 20. Many patients could thus be denied the most effective treatment for their infection through a misunderstanding.
And that medical ID information is not vetted by doctors:
The current validity of information on ID bracelets is also questionable; no company requires physician input into the wording on medical alert devices, although some recommend consultation with the primary care physician or healthcare provider for advice on what information to have engraved 21. Some companies advise a non‐mandatory (and chargeable) yearly update of information 3.
What have we learned?
There is no evidence that Medical ID jewelry saves lives.
The information on Medical ID jewelry is patient determined, and may or may not be accurate or up to date.
The medical ID industry is totally unregulated. Government should institute minimum standards to ensure the accuracy or appropriateness of the information provided.
I’m interested in readers’ experience with medical IDs, good and bad, so please feel free to share your anecdotes.
Has your life been saved by a medical ID?
What information is on your medical ID?
Any adverse experiences with medical ID?
N.B. In the course of this investigation I realized that my iPhone has a “medical ID” function that can be activated when the phone is locked and will display relevant medical information.
I added information with my emergency contacts, my medications and a few of my illnesses (including hyperskepticism) into the Medical ID section of the Apple Health app.
So, if you find me lying on the side of the road, look for my cell phone, push the two buttons on either side, wait a few seconds for the below screen, and perhaps you can save my life!
In March of 2017 AliveCor introduced Kardia Pro, a cloud-based software platform that allows physicians to monitor patients who use the Kardia mobile ECG device.
I have been utilizing the Kardia mobile ECG device since 2013 with many of my atrial fibrillation (AF) patients and have found it be very useful as a personal intermittent long term cardiac monitor. (see here and here)
I signed up for the Kardia Pro service about 3 months ago and all of my patients who purchased Kardia devices prior to March of 2017 have been migrated automatically to Kardia Pro by AliveCor.
Now (post March 2017), patients who acquire a Kardia device must sign up for the Kardia Pro service at $15 per month to connect with a physician.
I think this is money well spent and I’ll demonstrate how the service works with a few examples.
Monitoring Patients With Atrial Fibrillation
I saw a 68 year old man with persistent atrial fibrillation that was first diagnosed at the time of pneumonia in late 2017.
He underwent a cardioversion after recovering from the pneumonia but quickly reverted back to AF. His prior cardiologist offered him the option of repeat cardioversion and long term flecainide therapy for maintenance of normal sinus rhythm (NSR) but he declined.
When I saw him for the first time in the office a month ago I listened to his heart and to my surprise, noted a regular rhythm: an AliveCor recording in the office confirmed he was in NSR. The patient had been unaware of when he was in or out of rhythm
We discussed methods for monitoring his rhythm at this point which include a 24 Holter monitor, a 7 to 14 day Long Term Monitor, a Cardiac Event Monitor and a Mobile Cardiac Outpatient Telemetry device. These devices are helpful and although expensive are often covered by insurance. They require wearing electrodes or a patch continuously and the results are not immediately available.
I also offered him the option of monitoring his AF using a Kardia device with the recordings connected to me by Kardia Pro.
He purchased the device on his own for $99, downloaded the app for his smartphone and began making recordings.
I enrolled him in my Kardia Pro account and he received an email invitation with a code that he entered which connected his account with mine, allowing me to view all of his recordings as they were made.
When I log into my Kardia Pro account I can now view a graphic display of the recordings he has made with color coding of whether they were considered normal or abnormal by Kardia.
The patient overview page also displays BP information if the patient is utilizing certain Omron devices which work with Kardia.
The display shows that after our office visit he maintained NSR for 3 days (green dots) and then intermittently had ECG recordings classified as AF (yellow dots) or unclassified (black).
The more he used the device and got feedback on when he was in or out of rhythm the more he was able to recognize symptoms that were caused by AF.
I can click on any of the dots and six second strips of the full recording are displayed. In the example below I clicked on 2/27 which has both an unclassified recording (which is atrial flutter) and an AF recording
Clicking on the ECG strips brings up the full 30 second recording on a page that also allows me to assign my formal interpretation. In the example below I added atrial flutter as the diagnosis, changing it from Kardia’s unclassified (Kardia’s algorithm calls anything it cannot clearly identify as AF that is over 100 BPM as unclassified.)
The ECG can then be archived or exported for entry into an EHR.
The benefits of this patient being connected
to me are obvious: we now have an instantaneous patient-controlled method for knowing what his cardiac rhythm is doing whether he is having symptoms or not.
This knowledge allows me to make more informed treatment decisions.
The Kardia Pro Dashboard
When I log into kardia pro I see this screen.
It contains buttons for searching for a specific patient or adding a new patient. Adding new patients is a quick and simple process requiring input of patient demographics including email and birthdate.
From the opening screen you can click on your triage tab. I have elected to have all non normal patient recorded ECGS go into the triage tab.
Another patient’s Kardia Pro page shows that he records an ECG nearly every day and most of the time Kardia documents NSR in the 60s. Overall, he has made 773 recordings and 677 of them were NSR, 28 unanalyzed (due to brevity) , 13 unclassified and 55 showing AF.
Monitoring Rate Control In Patients With AF and Reversion Post-Cardioversion
Another patient I saw for the first time recently has had long-standing persistent AF. His previous cardiologist performed an electrical cardioversion a year ago but the patient reverted back to AF in 40 hours. Before seeing me he had purchased a Kardia mobile ECG device and was using it to monitor his heart rate.
After he accepted my email invitation to connect via Kardia Pro I was able to see his rhythm and rate daily. The Kardia Pro chart belowshows his daily heart rate while in atrial fibrillation. We utilized this to guide titration of his rate controlling medications. Such precise remote monitoring of heart rate in AF (which is often difficult to accurately assess by standard heart rate devices) obviates the need for office visits for 12 lead ECGs or periodic Holter monitors.
I performed a second cardioversion on him after which he made daily recordings documenting maintenance of NSR. With this system we can determine exactly when AF returns, information which will be very helpful in determining future treatment options.
Kardia Pro Plus Kardia Mobile ECG Creates Personal Intermittent Long Term Rhythm Monitor
There are many potential applications of the Kardia ECG device beyond AF monitoring (assessing palpitations, PVCs, tachycardia, etc.) but they are all enhanced when the device is combined with a good cardiologist connected to the device by Kardia Pro.
I’ve gotten spoiled by the information I get from my AF patients who are on Kardia Pro now. When they call the office with palpitations or a sense of being out of rhythm I can determine within a minute what their rhythm is wherever I am (excluding tropical beaches and mountain tops) or wherever the patient is (for the most part.)
On the other hand patients who are not on Kardia Pro have to come into the office for 12-lead ECGs. When they call I feel like my diagnostic tools are limited. Such patients usually end up getting one of the standard Long Term Monitoring (LTM) Devices. If I am fortunate, after a few days to weeks , the results of the LTM will be faxed to my office.
I am optimistic based on this early experience with Kardia Pro that ultimately this service in conjunction with the Kardia Mobile ECG device (or similar products) will replace many of the more expensive and inconvenient long term monitoring devices that cardiologists currently use.
The KardiaBand for Apple Watch from AliveCor has delivered on its unique promise of a medical grade single lead ECG recording made by placing your thumb on your wristwatch band.
The ECG recordings are equivalent in quality to those made by their previously available KardiaMobile (see my prior post here.) After more experience with the Band I think the ease of recording is superior to KardiaMobile and the ability to discriminate atrial fibrillation from normal sinus rhythm is similar to KardiaMobile.
By combining either a KardiaBand or a KardiaMobile device with Kardia’s SmartRhythm monitoring system for Apple Watch we now have the promise of personal monitoring to detect atrial fibrillation.
What is SmartRhythm?
SmartRhythm is AliveCor’s term for its system for monitoring your heart rate and activity levels in order to identify when your rhythm is abnormal.
The system “takes your heart rate and activity data gathered from the Apple Watch and evaluates it using a deep neural network to predict your heart rate pattern.”
The heart rate is obtained from the Apple Watch PPG sensor every 5 seconds. If it differs from what is predicted SmartRhythm notifies you to record an ECG.
If you’d like to learn more detail about the development of SmartRhythm and how it functions, AliveCor has an excellent informational piece here.
You can choose to have the Kardia SmartRhythm display come up whenever your Apple Watch awakens. It’s got information on your heart rate and activity over the preceding several hours
The AliveCor FAQ on SmartRhythm stresses that a notification does not always mean an abnormal rhythm. Clearly false positives can and will occur. The first day I wore my KardiaBand I had several of these.
Causes for false positives include exercise that Apple Watch couldn’t detect, stress or anxiety-in other words, situations where your heart rate is higher than predicted by how much activity you are doing.
The long term record of your SmartRhythm recordings resides on your iPhone . Here’s my record for the last week
Note that Kardia , in addition to tracking your heart rate, also shows you by the green, yellow and orange dots, the times that ECG recordings were made.
Green dots indicate recordings classified as normal and yellow as “unclassified.” In my case most of the unclassified recordings were due to heart rate >100 BPM associated with exercise.
There is one orange dot indicating that Kardia felt the ECG showed “possible atrial fibrillation.”
This happened when I took my Apple Watch off my wrist and put it on one of my patients who has permanent atrial fibrillation. I had him push on the KardiaBand sensor to make an ECG recording and it was correctly identified as atrial fibrillation.
Thus far I have had no notifications of “possible atrial fibrillation” while I have been wearing my watch thus the false positive rate appears acceptably low.
How Does SmartRhythm Perform During Exercise?
I checked out SmartRhythm’s ability to predict normal and abnormal heart patterns by wearing it during a session on my indoor bike trainer. The device did a good job of tracking both my heart rate and activity during the workout. You can view the most recent data by viewing your Apple Watch screen during the workout as below
Or for more detailed information you can view the complete history on your iPhone as below
The system accurately tracked my heart rate and activity (although AliveCor lists stationary bike as an activity that may result in false positives). During a session of weights after the aerobic workout despite erratic heart rates and arm movements it did not notify me of an abnormality. I also did 100 jumping jacks (which involves wildly flailing my arms) and the heart rate remained within the predicted boundaries.
What is more remarkable is that I was able while cycling at peak activity to make a very good quality ECG recording by taking my right hand off the handle bar and pushing my thumb down on the KardiaBand sensor on my left wrist.
This recording clearly displays p waves and is sinus tachycardia. It’s unclassified by Kardia because the rate is >100 BPM.
Afib Patient Experience
One of my patients last week, a 70 year old woman with paroxysmal atrial fibrillation, had already set up SmartRhythm monitoring on her Apple Watch.
I have this patient like many of my afibbers utilizing KardiaMobile to check an ECG when they think they are in afib.
However, she, like many of my afib patients, is totally unaware when her heart is out of rhythm. Such asymptomatic patients are alerted to the fact that they are in afib by detection of a rapid heart rate (from a heart rate tracking wearable or BP monitor) or an irregular heart beat (from BP monitor or by someone checking the pulse) or by a random recording of an ECG.
She’s started using SmartRhythm in the hopes that it will provide a reliable and early warning of when she goes into atrial fibrillation.
We discussed the possibility of stopping the flecainide she takes to maintain normal rhythm to test the accuracy of the SmartRhythm system for detecting atrial fibrillation in her but decided not to. She’s on an oral anticoagulant and therefore protected from stroke so development of atrial fibrillation will not be dangerous for her.
I eagerly await the first real world, real patient reports of SmartRhythm’s performance in atrial fibrillation detection.
If there are any afibbers out there who have had an episode of atrial fibrillation detected by SmartRhythm please let me know the details.
We need such anecdotes along with controlled trials to determine how useful SmartRhythm will be as a personal wearable system for detection of afib.
N.B. I’ve copied a nice section from AliveCor’s website which describes in detail the difference between measuring heart rate from the PPG sensor that all wearable devices use versus measuring the electrical activity of the heart with an ECG.
To understand how Kardia for Apple Watch works, let’s start by talking about your heart, how the Apple Watch and other wearable devices can measure your heart rate, and how an ECG is different from the information you get from a heart rate sensor alone.
Your heart is a pump. With each beat of your heart, blood is pumped through your arteries and causes them to expand. In the time between beats, your arteries relax again. On the underside of the Apple Watch is a sensor, called a photoplethysmogram (PPG), that uses green and infrared LEDs to shine light onto your skin, and detects the small changes in the amount of light reflected back as your arteries expand and relax with each beat of your heart. Using this sensor, the Apple Watch can tell how fast your heart is beating, and how your heart rate changes over time.
But, your heart rate does not tell everything there is to know about your heart. The PPG sensor on the Apple Watch can only see what happens after each heartbeat, as blood is pumped around your body. It can’t tell you anything about what is making your heart beat, or about what happens inside your heart during each beat. An ECG is very different, and tells you a lot more!
An ECG measures the electrical activity in your heart muscles. It detects the small pulse of electricity from the sinoatrial node (the body’s natural pacemaker, which normally initiates each heartbeat) and the large electrical impulses produced as the lower chambers of the heart (the ventricles) contract and relax. By looking at an ECG, a doctor can discern a wealth of information about the health and activity of your heart muscle, much more than you can tell from your heart rate alone. ECGs are the required gold standard for diagnosis of arrhythmias and many cardiac abnormalities, and can even be used to see evidence of acute heart attacks and even events that have occurred in the past.
Research has shown that taking frequent ECGs increases the likelihood of detecting certain arrhythmias, and decreases the mean time to diagnosis.
The skeptical cardiologist has been evaluating the Kardia Band from AliveCor which allows one to record single lead medical grade ECGS on your Apple Watch. What follows is my initial experience with setting up the device and using it to make recordings.
After ordering my Kardia Band for Apple Watch on 11/30 from AliveCor the device appeared on my door step 2 days later on a Saturday giving me most of a Sunday to evaluate it.
What’s In The Box
Inside the box I found one small and one large black rubber wrist watch band
The larger one had had a small squarish silver metallic sensor and the smaller one had a space to insert a sensor. It turns out my wrist required the smaller band and it was very easy to pop out the sensor and pop it into the smaller band.
After replacing my current band with the Kardia band (requires pushing the button just below the band and sliding the old band out then sliding the new one in) I was ready to go.
The Eternal fiancée did not complain about the appearance of the band so I’m taking that to mean it passes the sufficiently stylish test. She did inquire as to different colors but it appears AliveCor only has one style and one color to choose from right now.
I have had problems with rashes developing with Apple’s rubbery band and switched to a different one but thus far the Kardia band is not causing wrist irritation.
I didn’t encounter any directions in the box or online so I clicked on the Kardia app on the watch and the following distressing message appeared.
Prior to 11/30 Kardia Band only worked in certain countries in Europe so I suspected my AliveCor app needed to be updated.
I redownloaded the Kardia app from the Apple App Store , deleted it off my Watch and reinstalled it.
I was thrilled when the app opened up and gave me the following message
However, I was a little puzzled as I was not aware that setting up Smart Rhythm was a requirement to utilize the ECG recording aspect of Kardia Band. Since I have been granted a grandfathered Premium membership by AliveCor I knew that I would have access to Smart Rhythm and went through the process of entering my name and email into the Kardia app to get this started.
Alas, when the Watch Kardia app was accessed after this I continued to get the same screen. Clicking on “need help” revealed the following message:
Bluetooth was clearly on and several attempts to restart both the watch and the iPhone app did not advance the situation.
I sent out pleas for assistance to AliveCor.
At this point the Eternal Fiancee had awoken and we went to Sardella for a delightful brunch . I had this marvelous item:
Later on that day I returned to my Kardia Band iPhone and deinstalled, reinstalled , reloaded and restarted everything.
The First Recording
At this point it worked and I was able to obtain my first recording by pushing the record ECG button and holding my thumb on the sensor for 30 seconds.
I’ve made lots of recordings since then and they are good quality and have accurately recognized that I am in normal sinus rhythm.
The Smart Rhythm component has also been working. Here is a screen shot of today’s graph.
You’l notice that the Smart Rhythm AI gave me a warning sometime in the morning (which I missed) as it felt my rhythm was abnormal. I missed making the recording but am certain that I was not in afib.
Comparison of the Kardia Band recording (on the right) versus the separate Kardia device recording (on left) shows that they are very similar in terms of the voltage or height of the p waves, QRS complexes and T waves.
I felt a palpitation earlier and was able to quickly activate the Kardia Watch app and make a recording which revealed a PVC.
In summary, after some difficulty getting the app to work I am very pleased with the ease of recording, the quality of the recording and the overall performance of Kardia Band. The difficulties I encountered might reflect an early adoption issue which may already be resolved. Please give me feedback on how the device set up worked for you.
I’ll be testing this out on patients with atrial fibrillation and report on how it works in various situations in future posts.
After more experience with the Smart Rhythm monitoring system which I think could be a fantastic breakthrough in personal health monitoring I’ll give a detailed analysis of that feature.
AliveCor has finally gotten approval from the FDA to release its Kardia Band in the United States.
The skeptical cardiologist is quite excited to get his hands (or wrist) on one and just gave AliveCor $199 to get it.
The device incorporates a mobile ECG sensor into a wrist band that works with either 42 or 38 mm Apple watches. I’ve written extensively about AliveCor’s previous mobile ECG product (here and here) which does a good job of recording a single lead ECG rhythm strip and identifying atrial fibrillation versus normal rhythm,
Hopefully, the Kardia Band will work as well as the earlier device in accurately detecting atrial fibrillation.
According to this brief video to make a recording you tap the watch screen then put your thumb on the sensor on the band.
The app can monitor your heart rate constantly and alerts you to make a recording if it thinks you have an abnormal rhythm.
I was alerted to the release of Kardia by Larry Husten’s excellent Cardio Brief blog and in his post he indicates that the alert service , termed Smart Rhythm, requires a subscription of $99 per year.:
AliveCor simultaneously announced the introduction of SmartRhythm, a program for the Apple Watch that monitors the watch’s heart rate and activity sensors and provides real-time alerts to users to capture an ECG with the Kardia Band. The program, according to an AliveCor spokesperson, “leverages sophisticated artificial intelligence to detect when a user’s heart rate and physical activity are out of sync, and prompts users to take an EKG in case it’s signaling possible abnormalities like AFib.”
The Kardia Band will sell for $199. This includes the ability to record unlimited ECGs and to email the readings to anyone. The SmartRhythm program will be part of the company’s KardiaGuard membership, which costs $99 a year. KardiaGuard stores ECG recordings in the cloud and provides monthly summary reports on ECGs and other readings taken.
AliveCor tells me my Kardia Band will be shipped in 1-2 days and I hope to be able to give my evaluation of it before Christmas.
Please note that I paid for the device myself in order to avoid any bias that could be introduced by receiving largesse from AliveCor.
N.B. Larry Husten’s article includes some perspective and warnings from two cardiologist and can be read here.
Another article on the Kardia Band release suggests that the Smart Rhythm program at $99/ year is a requirement.
Perhaps, AliveCor’s David Albert can weigh in on whether the annual subscription is a requirement for making recordings or just allows the continuous monitoring aspect.
The Skeptical Cardiologist is a strong proponent of empowering patients with atrial fibrillation by utilizing personal cardiac rhythm devices such as Afib Alert or AliveCor’s Kardia.
I’ve written about my experiences with the initial versions of the Kardia mobile ECG device and the service it provides here and here.
I have been monitoring dozens of my afib patients using AliveCor’s Physician Dashboard.
Recently AliveCor changed fundamentally the way their app works such that for new users much of the functionality I described in my previous posts now requires subscribing to their Premium service which costs $9.99 per month or $99 per year.
What Has Changed With The Kardia App
The Kardia device which works with both iOs and Android smart
phones is unchanged and still generates a “medical-grade” single lead rhythm strips which appears within the Kardia app.
The app still is reasonably accurate at identifying atrial fibrillation or normal heart rhythms and offers a fee-based service for interpretation of unclassified ECGs.
However, for new purchasers of Kardia, the capability to access, email or print prior ECG recordings has gone away. Prior to March of this year, Kardia users could access prior ECG tracings which were stored in the cloud by touching the “Journal” button on the app. These older tracings could be emailed and they were available through the cloud for a physician like myself to review at any time.
Now new Kardia purchasers will find that when they make an ECG recording they have the option to email a PDF of the ECG but once they hit the DONE button it is gone and is not stored anywhere.
For my patients purchasing after March, 2017 this means that unless they purchase Kardia Premium service I will not be able to view their ECG recordings online.
An AliveCor account executive summarized for me the changes as follows:
We added a significant number of features over the past year and a half, and grandfathered all users on March 16th, 2017. New users now have the option to download and use Kardia for free, but the premium services are $9.99/mo or $99/year. Kardia Premium allows unlimited storage and history of their EKGs, summary reports with longitudinal data, blood pressure monitoring and tracking weight and medication.
Why Journal Functionality Is Important
If you purchased your AliveCor/Kardia device prior to March 16th, 2017 ago the journal functionality still works. Let’s call such customers “Journal Grandfathered”.
This Journal functionality is important in a number of ways:
My Journal Grandfathered patients can bring their phones with them during an office visit and we can review all of their ECG tracings.
Journal gGandfathered Kardia users can email their old tracings to their physicians or to anyone they wish (even the skeptical cardiologist!). They can also print them out and save PDFs of the tracings.
I can view through my online physician account all of my Journal Grandfathered patients. This means any time a patient of mine makes a recording that is unclassified or suggests atrial fibrillation I can be notified and immediately view it online.
This fundamental change took place as AliveCor attempts to convince purchasers of the Kardia device to use their Premium service.
Why AliveCor Changed The Kardia App Function
Dr. David Albert, inventor and cardiologist and the founder of AliveCor was kind enough to talk with me about this change.
He indicates that of the 150,000 AliveCor users, 10,000 are now using the Kardia Premium service. About 20% of new users elect Kardia Premium.
Prior to the change all AliveCor users had their old ECG recordings stored in the cloud in a HIPPA compliant fashion. This free service was costing AliveCor quite a bit and the company felt it was best to switch to a subscription service to provide this secure cloud storage.
With the change to the (relatively inexpensive) subscription service, patients will get additional features. As the AliveCor account executive described:
Kardia Premium allows unlimited storage and history of their EKGs, summary reports with longitudinal data, blood pressure monitoring and tracking weight and medication.
I’ve looked at the Premium service and it seems quite useful when combined with a connected physician utilizing Kardia Pro. I’ll evaluate the Premium service and the physician Kardia Pro service further and write a full post on its features in the near future.
If you are not grandfathered and want to stick with the Basic Kardia service you still have an immensely useful and inexpensive device which allows personal detection of your cardiac rhythm. Just remember to email yourself the ECG recording you just made before you hit DONE.