Tag Archives: AliveCor

Atrial Fibrillation In The Time of Coronavirus: A Call For More Personal Remote ECG Monitoring

What is the best strategy for doctors and patients dealing with atrial fibrillation during the COVID-19 pandemic?

Clearly, at this time everyone needs to minimize visits to the doctor’s office, emergency room, urgent care center or hospital. But patients with paroxysmal atrial fibrillation by definition will have periodic spells during which their heart goes out of rhythm and many of these will occur during this period when we want to minimize contact with individuals outside the home.

In my practice, we are able to manage the majority of these episodes remotely by using a combination of personal ECG monitoring, online cloud ECG review capability, and home adjustment of medications.

Given the presence of coronavirus in the community and the potential for overload of acute care medical resources, outpatient/home management of atrial fibrillation is more important than ever.

I have described in detail in previous posts how we utilize Alivecor’s Kardia device in conjunction with the cloud-based KardiaPro subscription service to manage our afib patients remotely.  (See here and here.) The Apple Watch ECG can also be utilized for this purpose but is more expensive than Kardia and has no online review service.

With this approach we are able to minimize ER visits and hospitalizations. In addition, use of long-term monitors (which also requires a visit to an outpatient center for hook-up) has been greatly reduced.

Given heightened anxiety during the pandemic we are also seeing many patients experiencing palpitations, which are not due to their atrial fibrillation. These can be due to benign premature ventricular contractions or premature atrial contractions.

If an afib patient calls with symptoms of palpitations or rapid heart beat and they have a Kardia device or Apple Watch ECG we can review the recorded ECG, and can quickly make a determination of the cause and best treatment. If they don’t have one of these devices we have no idea what the cause is or the best treatment.

General Advice For Afib Patients 

Obviously, it would be great if patients don’t have episodes of afib during the pandemic.

Paying attention to the eight lifestyle factors which influence afib occurrence I’ve recently posted on is even more important during this stressful period. In particular, afib patients should be limiting the inclination to consume more alcohol and utilizing healthier ways to reduce stress.

Regular exercise has demonstrated benefits in reducing afib episodes and also reduces stress. Gyms are closed or closing, but with spring arriving, outside exercise is always possible. Even if you don’t have exercise equipment in your home there are many exercises you can do inside that provide cardio, strength, and flexibility training. Consider bodyweight exercises, jumping rope, hoping on to a small chair, or go find your old Richard Simmons exercise VHS tape. My wife and I have been enjoying the Seven app lately which takes us through a variety of exercises without the need for equipment. There are tens of thousands of exercise videos on YouTube.

Some afibbers find that meditation or relaxation apps or yoga helps with stress control.

Finally, make sure you have plenty of your prescription medications on hand and that you take them as prescribed without fail. Many pharmacies have home-delivery available for prescriptions.

Regarding medications, please note that good blood pressure control also reduces afib recurrence. Do not stop ACE inhibitors or ARBs as I discussed here.

A Call For More Self Monitoring

Given the importance of staying home right now, afib patients who do not have a method for self monitoring their heart rhythms should consider acquiring a Kardia device or Apple Watch.

Antifibrillatorily Yours,

-ACP

N.B. As I’ve mentioned multiple times I have no connections, financial or otherwise to Apple or Alivecor.

KardiaMobile, the original single lead personal ECG is selling for $84 right now. It’s available also on Amazon.

In my opinion, there is no compelling reason to prefer the Kardia6l, which costs $149 over the single lead KardiaMobile.

Both of these devices work with a Google or iPhone app which is free. To store recorded ECGs on Alivecor’s cloud service requires a subscription fee.

When I enroll my patients into KardiaPro I send them an email invitation which allows them to purchase the KardiaMobile plus have one year of cloud storage and connection to my KardiaPro dashboard for $120. Thereafter the one year KardiaPro service is $60/year.

Apple Watch 5 starts at $399. ECGS are stored in the iPhone app. No cloud storage. ECGs can be emailed as PDF.

Patients with Apple 4 Watches or later can send a PDF of their ECG via email or fax to their cardiologist (https://support.apple.com/en-us/HT208955). Check with your cardiologist if they can view a PDF.

NOTE: Apple has closed all of their retail stores outside of Greater China until March 27. Online stores are open at www.apple.com, or you can download the Apple Store app on the App Store so you can still buy an Apple Watch or an iPhone too.

Cheaper personal ECG devices are available. I’ve reviewed several of these and don’t recommend them. (See here and here.)

Thanks to Mark Goldstein  and Dan Field for review/editing of this post.

Omron Complete Consolidates and Simplifies Home ECG and Blood Pressure Monitoring

The skeptical cardiologist has been testing out a unique and ingenious device which allows the simultaneous measurement of two key cardiovascular parameters: blood pressure and heart rhythm.  Omron partnered with AliveCor to create the Complete which is the first combination blood pressure monitor and electrocardiogram monitor.

Given that Alivecor’s Kardia Mobile ECG device is capable of accurately identifying atrial fibrillation, the Complete offers patients the ability to monitor for the two biggest treatable risk factors for stroke: atrial fibrillation and hypertension.

I have evaluated the Complete in both office and home settings and find it to be easy to use and highly reliable.

The main component of Complete is an attractive unit that measures 9 by 4 by 5 inches, weighs a little over a pound and combines the blood pressure monitor and the AliveCor sensors. It ships with a wide-range D-ring BP cuff which fits 9 to 17-inch upper arms and runs on 4 AA batteries.

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Recording Blood Pressure and ECG

You can easily record just blood pressure using the device right out of the box (after inserting the included 4 AA batteries.)  However, the full capabilities of the device are realized in conjunction with Omron’s Connect US/CAN Smartphone app which can be downloaded for free. Once paired with the app, the device can record and transfer ECGs along with blood pressure measurements to the app and the cloud.

The process of recording a single-lead ECG on the Complete  is nearly identical to the process when using the AliveCor Kardia mobile ECG device except that there are four sensors for Complete versus the two sensors on the Kardia device.

After opening the Omron app on your smartphone and pressing the “Record BP and EKG” button, you place the smartphone horizontally on the Complete cradle and put your hands on the sensors with thumbs on the tops sensors and 2-3 fingers on the lateral sensors as illustrated below.

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Once the device senses a good signal the ECG recording will automatically begin and continue for 30 seconds. It’s important to stay very still and quiet during this time to optimize the recording quality.

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Like the Kardia device if your fingers are too dry, electrical contact may be suboptimal. This can be fixed by wetting your fingers with an alcohol wipe, a spray from a sanitizer bottle or just water from the tap. See my discussion on this here.

I found the 4 sensors plus the stability of the device the sensors reside in made for a higher percentage of high-quality ECG recordings on the Complete versus the smaller Kardia device. Stability on the Kardia device is a particular issue for the elderly and we were able to consistently obtain good quality ECG recordings in my office on the frail and elderly with the Complete.

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Typical, easily-obtained, high-quality ECG recording obtained from the Complete

The PDF of the ECG can be emailed to yourself for storage or to your physician for his review. With a Premium plan upgrade, you can store the ECGS online or utilize KardiaPro which shares your BP and ECG data through the cloud with your physician.

Blood Pressure Plus ECG

You can choose to record BP and ECG separately or at the same time. To record both, place the BP cuff on your upper arm,  push the start/stop button and then put your fingers on the ECG sensors. While the ECG is recording, the BP cuff inflates and obtains the BP measurement.

As always when taking BP it is important to make sure the cuff is at the level of the heart.

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Using KardiaPro Online Dashboard With Complete

Many of my patients have both atrial fibrillation and hypertension. For them, the KardiaPro dashboard provides a unique online monitoring system that allows me to view both their blood pressure recordings and their ECG recordings in one spot.

Omron’s Complete now simplifies and consolidates the process of recording BP and ECG for such patients. A typical KardiaPro report from one of my combined AF and hypertensive patients  appears below.

kardiapro bp and ecg

Where Does Complete Fit In The Home Monitoring Universe?

I see Complete serving in two important areas.

The first is as a consolidated unit for patients with atrial fibrillation and hypertension. Complete provides an easy, quick, and stable method for these patients to home monitor their BPs and their rhythm.

The second area is in physician offices. The ability to record a high quality, medical-grade ECG simultaneously with blood pressure will improve the physician’s ability to screen for hypertension and rhythm abnormalities in an efficient manner.

Completely Yours,

-ACP

N.B. Looking at the Omron website today I note that Complete is selling for $159.99, a 20% discount.

AliveCor’s Kardia Mobile ECG Accurately Identifies Atrial Fibrillation >120 BPM

The skeptical cardiologist revealed recently that the  Apple Watch (AW) ECG app is incapable of identifying atrial fibrillation (AF) if the heart rate is greater than 120 beats per minute. It labels these recordings as “inconclusive”.

Since it is common for AF to present at rates >120 BPM, AW ECG will fail to notify many (if not most) of its users that they are in AF.

AliveCor’s Kardia mobile ECG device (both the single lead and the six lead), on the other hand, has no problems identifying AF >120 BPM. I have found that the Kardia ECG was highly accurate in patients with rapid AF from using the device in hundreds of my patients since 2013.

After writing about the AW AF flaw I opened my KardiaPro dashboard which connects to the online ECG recordings each of my patients has made.

Two of my patients with paroxysmal AF had gone into AF in the last 2  days and made recordings.

Both of them had rates > 120 BPM. In both cases, Kardia had easily made the diagnosis. AW would have declared these “inconclusive.”

Patients should be aware of this AW AF flaw. The absence of a declaration of possible AF on the AW ECG should not reassure anyone of the absence of AF.

AW users should have their high rate recordings reviewed by a cardiologist.

Alternatively, they could purchase a Kardia device and utilize it for heart rates over 120 BPM.

Tachyagnostically Yours,

-ACP

An In-depth, Objective Comparison of Mobile ECG Devices: Emay versus Kardia

The skeptical cardiologist has been a huge advocate of personal mobile ECG monitoring to empower patient’s in understanding/monitoring their heart rhythm.

The deserved leaders in this field are the Apple Watch (4 and later) and Alivecor’s Kardia device which comes in single-lead and six-lead flavors.

Both Apple and AliveCor have gotten FDA approval for their mobile ECG device and have a body of published studies supporting their accuracy.

In contrast, there are a number of “copy-cat” mobile ECG devices which have been feeding on the success of Apple Watch and Kardia but do not have the bona fides the two leaders have.

I reviewed the SonoHealth ECG here and found it sorely lacking in comparison to Kardia in terms of accuracy of diagnosis and quality of recordings, the two most important aspects of a personal ECG monitor.

Dan Field, a physician  and reader of my blog, has been evaluating a device similar to the SonoHealth ECG made by Emay.

He has provided a point by point comparison of the two  devices in the chart below

Emay versus Kardia

His summary:

“The Kardia6L was clearly superior in almost every way except for price and even that was within the margin of error. ”

It should be noted that the single lead Kardia mobile ECG is actually cheaper than the Emay and retails for $99.

Let The (Mobile ECG) Buyer Beware

I ended my post reviewing SonoHealth’s ECG with a warning which applies equally to the Emay device:

The SonoHealth EKGraph is capable of making a reasonable quality single lead ECG. Presumably all the other devices utilizing the same hardware will work as well.

However, the utility of these devices for consumers and patients lies in the ability of the software algorithms to provide accurate diagnoses of the cardiac rhythm.

Apple Watch 4 and AliveCor’s Kardia mobile ECG do a very good job of sorting out atrial fibrillation from normal rhythm but the SonoHealth EKGraph does a horrible job and should not be relied on for this purpose.

The companies making and selling the EKGraph and similar devices have not done the due diligence Apple and AliveCor have done in making sure their mobile ECG devices are accurate.  As far as I can tell this is just an attempt to fool naive patients and consumers by a combination of marketing misinformation and manipulation.

I cannot recommend SonoHealth’s EKGraph or any of the other copycat mobile ECG devices. For a few dollars more consumers can have a proven, reliable mobile ECG device with a solid algorithm for rhythm diagnosis. The monthly subscription fee that AliveCor offers as an option allows permanent storage in the cloud along with the capability to connect via KardiaPro with a physician and is well worth the dollars spent.

Skeptically Yours,

-ACP

 

Black Friday Sales Even A Skeptic Can Embrace

The skeptical cardiologist refuses to buy anything on Black Friday.  I don’t want to be manipulated into buying something just because it is cheaper for a while.

However, I have noticed that many of the cardiovascular products I recommend or have written about are substantially discounted today.

I present them in no particular order.

The QardioArm BP cuff which I have called the iPhone of BP devices is marked down from $99 to $69$ for a “limited time.”

While it is portable, stylish and accurate it is not, as Qardio ludicrously claims, “four times more effective at lower blood pressure.”

Omron, whose blue-tooth enabled BP devices connect to an online dashboard your doctor can visualize is offering 30% off through 12/31/2019 on all devices on their website.

I presume this includes the delightful Omron Evolv.

It may include the Omron Heart Guide, a wrist-based watch which measures BP. I’ll be writing my review of this device soon.

I’ve written a lot about the value of AliveCor’s Kardia Mobile ECG and the single lead device is marked down from $99 to $ 84 for Black Friday.

Finally, one of my favorite gadgets (see here), the Keyto ketone breath sensor sent me this email this morning.

I can’t vouch for the Keyto chocolate shake or the basil pesto that they are now including with Black Friday sales but I love the Keyto.

By the way, it wasn’t clear to me when I first got the Keyto device what kind of diet Keyto promotes. They favor a plant-based keto (with fish) diet which they consider “heart healthy.”  More on this down the line.

Appositely Yours,

-ACP

Atrial Fibrillation Detection, Personal ECG Monitoring and Ablation: A Patient’s Story

One of the joys of writing this blog is the communication it allows me with discerning  individuals and patients across the planet. One such reader, Mark Goldstein, discovered he was in atrial fibrillation after purchasing an Apple Watch 4.

He now utilizes both the Kardia Mobile ECG and the Apple Watch to aid in his personal monitoring of his atrial fibrillation and has been actively pursuing a rhythm control strategy under the care of his electrophysiologist.

I asked him to share with my readers his experience which recently culminated in an ablation.

What follows is his description with my editorial comments in green.


December 2018 I bought a crazy, expensive Apple Watch. That watch may have saved my life. I spend much of my days at a treaddesk (a combination desk and treadmill). I was curious to find out how much exercise I was doing. I bought the watch, put it on, and starting walking as I do almost every day. Two hours later the watch had an alarm. It was warning me about something called “atrial fibrillation,” It said, “your heart has shown signs of an irregular rhythm.” What! I never heard of afib before. I quickly learned about it. Heart palpitations, no. Pain/pressure in the chest, no. Sweaty, faint, dizzy, etc., no, no. no. I checked the box for tired but I assumed it was because of the amount of exercise I was doing.

The next day I was fortunate that I had a physical scheduled a year ago. I told my doctor that my “crazy, expensive watch” thinks I have afib. My doctor laughed, telling me about how he had checked and probed every part of my body for the last 20 years (the probing part I remembered well). As the exam was concluding, he was puzzled by the afib warning so he grabbed my wrist to check my pulse. A few seconds later he was asking the nurse to give me an EKG. Darn, the watch was correct (and for me it was correct 99% of the time when I had afib and when I was normal – praise to Apple).

Recording from Mark’s Apple Watch 4 showing atrial fibrillation with controlled ventricular response. Heart rate is only 82 beats per minute. The AW algorithm correction identifies atrial fibrillation.

(This is a great example of how atrial fibrillation can be missed by the routine office physical examination. Some patients, especially those with non-rapid heart rates (due to rate slowing meds like beta-blockers or to intrinsically  slow conduction of electrical impulses) are minimally symptomatic and their pulses don’t feel that irregular. Because the first symptom of afib can be stroke I am an advocate of screening)

Shortly I got to meet a cardiologist (like Dr. Pearson, they are all nice people). Another EKG, afib confirmed. As we were talking about my symptoms or lack of symptoms, he said that afib was a bit like Eskimo’s describing snow. Each snowflake is unique and each afib patient is unique. I was in persistent afib. Probably had been in this state for two or three years since my heart rate jumped while sleeping, exercising, and at rest.

(Each afib experience is unique but not all cardiologists are nice people. Mark has been fortunate.)

The treatment plan was a cardioversion, an electrical shock to the heart, or as my cardiologist described it “like rebooting a computer.”

(See my post on cardioversion here.)

As a tech person, I understood that. The risk of not fixing my afib was five times the likelihood of a stroke. The risks were minimal so I chose the cardioversion.

(A common misconception is that ablation or cardioversion eliminates or substantially lowers the risk of stroke in afib. This is not the case. I’ll devote a future post to delve into this issue.)

Cardioversion one lasted four days before my Apple Watch started to detect afib.

(I’ve described in detail how helpful patient utilization of personal ECG monitoring is in letting me know the rhythm status of patients prior to and following cardioversion here.)

The cardiologist next step was cardioversion two along with a drug to help with rhythm control. Number two lasted a month before I saw my heart rate jump again. I thought something was wrong even though my watch was not detecting afib. Another EKG, this time the result was aflutter. The cardioversions were indeed like a reboot of the computer. If you have a virus on your computer, a reboot may be a temporary fix but eventually the virus will return.

(There are many drugs whose purpose is to suppress the recurrence of atrial fibrillation. Mark was prescribed the extended release version of propafenone, a Type IC antiarrhythmic drug (AAD)  similar in efficacy and side effects to flecainide. Type IC AADs should only be used in patients with normal left ventricular function (which was demonstrated in Mark by an echo) and without significant coronary artery disease (typically proven by a negative stress test).

To Ablate Or Not To Ablate

Now I got to meet an electrocardiologist. He said my afib would return and recommended an ablation. He said it was unlikely to be a permanent cure but it would help.

The aflutter disappeared after a day or so. I thought my afib was gone too but should I have an ablation? Ablations are relatively safe but since I was afib free why have the procedure?

I purchased the new Kardia Mobile six-lead portable EKG, a miracle of technology. Highly recommended for peace of mind. Just like my watch, I was seeing normal sinus rhythm. So why get an ablation?

A cardiologist had a YouTube video talking about the decision to have an ablation or any medical procedure. How will it affect the quality of your life or the quantity (how long will you live). This was a simple analysis and I like simple. I heard from my cardiologist that the evidence is that an ablation will unlikely extend my life nor will it reduce my lifespan. It was likely to not affect my lifespan. I confirmed this via independent research (be an informed patient, your outcomes will be better). See Dr Pearson’s articles about the CABANA study and the scientific evidence on ablation).  So an ablation and quantity of life were neutral.

Importance Of Quality Of Life

Quality of life was more interesting. Could I do the things wanted to do with my life? Did afib affect my day-to-day life? Could I walk up a couple of flights of stairs without breathing hard? Was I getting tired at 10AM? Could I exercise? At the time, the answer was easy. I could do everything I wanted to do. The afib affect was just about zero except for blood thinner drugs which I suspect I will take forever. No ablation.

Then “the day.” I woke and checked my sleep app on my phone. Heart rate at night jumped. Hmm! I went to the gym. My heart rate while walking jumped too. I did 30 seconds of high-intensity exercise and my heart rate monitor said 205 beats per minute. My heart was beating so hard I had to sit for five minutes. I knew something was wrong. Then I climbed a couple of flights of stairs, something that would never bother me. I felt a shortness of breath. I knew my afib was back. I also knew that the quality of my life was now being affected. I could not do things I wanted to do. My watch and Kardia Mobile EKG confirmed what I knew.

I called my electrocardiologist and scheduled an ablation. He was right. Afib would return.

(Mark tells me that he was taken off his propafenone one month after the second cardioversion because “the PA said I no longer needed it since I was in sinus rhythm.” My practice would have been to continue the propafenone as long as well tolerated and effective in suppressing afib recurrence. In my experience, the recurrence of Mark’s afib may not have been a failure of medical therapy. I treat patients similar to Mark by continuing the anti-arrhythmic drug since the minimal risks are lowered by regular monitoring and I regularly see maintenance of SR.”)

(Other antiarrhythmic medications were mentioned to Mark but as they required a 3 day hospital stay he was not interested.)


Stay tuned: Part two Of Mark’s post will be about the ablation procedure which he recently underwent.

Skeptically Yours,

-ACP

Mark Goldstein works in the field of cybersecurity in the WashingtonDC area and can be contacted at https://www.linkedin.com/in/markhgoldstein/

Which Ambulatory ECG Monitor For Which Patient?

The skeptical cardiologist still feels that KardiaPro has  eliminated  use of long term monitoring devices for most of his afib patients

However not all my afib patients are willing and able to self-monitor their atrial fibrillation using the Alivecor Mobile ECG device. For the Kardia unwilling and  many patients who don’t have afib we are still utilizing lots of long term monitors.

The ambulatory ECG monitoring world is very confusing and ever-changing but I recently came across a nice review of the area in the Cleveland Clinic Journal of Medicine which can be read in its entirety for free here.

This Table summarizes the various options available. I particularly like that they included relative cost. .

The traditional ambulatory ECG device is the “Holter” monitor which is named after its inventor and is relatively inexpensive and worn for 24 to 48 hours.

The variety of available devices are depicted in this nice graphic:

For the last few years we have predominantly been using the two week “patch” type devices in most of our patients who warrant a long term monitor. The Zio is the prototype for this but we are also using the BioTelemetry patch increasingly.

The more expensive mobile cardiac outpatient telemetry (MCOT) devices like the one below from BioTel look a lot like the patches now. The major difference to the patient is that the monitor has to be taken out and recharged every 5 days. In addition, as BioTel techs are reviewing the signal from the device they can notify the patient if the ECG from the patch is inadequate and have them switch to an included lanyard/electrode set-up.

The advantage of the patch monitors is that they are ultraportable, relatively unobtrusive and they monitor continuously with full disclosure.

The patch is applied to the left chest and usually stays there for two weeks (and yes, patients do get to shower during that time) at which time it is mailed back to the company for analysis.

Continuously Monitoring,

-ACP

AliveCor’s KardiaBand Will No Longer Be Sold And Smart Rhythm Is No More

The skeptical cardiologist was quite enthusiastic about AliveCor’s Kardia Band for Apple Watch upon its release late in 2017.

I was able to easily make high fidelity, medical grade ECG recordings with it and its AI  algorithm was highly accurate at identifying atrial fibrillation  (see here). This accuracy was subsequently confirmed by research.

Many skepcard readers spent $200 dollars for the Kardia Band and had found it to be very helpful in the management of their atrial fibrillation.

However, in December of 2018 Apple added ECG recording to its Apple Watch 4, essentially building into the AW4  the features that Kardia Band had offered as an add on to earlier Apple Watch versions.

In my evaluation of the Apple Watch I found it to be “an amazingly easy, convenient and straightforward method for recording a single channel ECG” but its algorithm in comparison to AliveCor’s yielded more uncertain diagnoses.

Given it size, prominence and vast resources, Apple’s very publicized move into this area seemed likely to threaten the viability of AliveCor’s Kardia Band.

But then-interim CEO (and current COO)  Ira Bahr later told MobiHealthNews that his company’s broader business wasn’t threatened by its new direct competitor.

“We’re not convinced that Apple’s excellent, engaging product is a competitor yet,” he said in February. “We believe that from a price perspective, this product is least accessible to the people who need it most. If you’re not an Apple user, you’ve got to buy an Apple Watch, you’ve got to buy an iPhone to make the system work. So their technology is excellent, but we think the platform is both complicated and expensive and certainly not, from a marketing perspective, targeting the patient populations we target.”

Indeed, AliveCor’s Mobile ECG device and its recently released 6 lead ECG are doing very well but the threat to the viability of KardiaBand was real and MobiHealth News announced Aug. 19 that AliveCor had officially ended sales of the Kardia Band.

An AliveCor representative told MobiHealthNews that the company “plans to continue supporting KardiaBand indefinitely” for those who have already purchased the device. The company’s decision was first highlighted by former MobiHealthNews Editor Brian Dolan in an Exits and Outcomes report.

Mr. Bahr has confirmed to me that AliveCor does plan to continue supporting KardiaBand indefinitely. This includes replacement of KardiaBand parts.

Did Apple Kill Smart Rhythm?

The informed reader who notified me of AliveCor’s decision also notes:

The official reason is that they could not keep up with the Apple Watch updates and therefore the Smart Rhythm feature did not work properly.

I think many of us knew from the beginning that smart rhythm was not very accurate But in spite of that the Kardia band provided a valuable convenience over their other products.

It does appear that Smart Rhythm is no more.

AliveCor’s website was updated 6 days ago to state that Smart Rhythm was discontinued:

” due to changes beyond our control in the Apple Watch operating system, which caused SmartRhythm to perform below our quality standards”

Likely, as my reader was told, the frequent  AW4 updates plus the lack of a large KardiaBand user base made it unprofitable for AliveCor to continue to support Smart Rhythm.

Smart Rhythm, of course was AliveCor’s method for watch-based detection of atrial fibrillation. It clearly had limitations, including false positives but given AliveCor’s track record of dedication to high quality and accuracy I assumed it would improve over time..

Apple, on December 6, 2018  with the release of its watchOS 5.1.2 for AW4 announced its own version of Smart Rhythm at the same time it activated the ECG capability of AW4.

Apple called this feature “the irregular rhythm notification feature” and cited support for its accuracy from the widely ballyhooed Apple Heart Study (which I critiqued here.)

The irregular rhythm notification feature (TIRNF)was recently studied in the Apple Heart Study. With over 400,000 participants, the Apple Heart Study was the largest screening study on atrial fibrillation ever conducted, also making it one of the largest cardiovascular trials to date. A subset of the data from the Apple Heart Study was submitted to the FDA to support clearance of the irregular rhythm notification feature. In that sub-study, of the participants that received an irregular rhythm notification on their Apple Watch while simultaneously wearing an ECG patch, 80 percent showed AFib on the ECG patch and 98 percent showed AFib or other clinically relevant arrhythmias.

Despite widely publicized reports of lives being saved by TIRNF we still don’t know whether its benefits outweigh its harms. It is not clear what its sensitivity is for detecting atrial fibrillation and I have reported one patient who was in atrial fibrillation for 3 hours without her AW4 alerting her to its presence.

For AW4 users, absence of an alert should not provide reassurance that your rhythm is normal.

Thus is does appear that the Goliath Apple hath smote the David AliveCor in the watch-based afib battle. This does not bode well for consumers and patients as I think as competition in this area would make for better products and more accountability.

Philorhythmically Yours,

-ACP

N.B.

Per AliveCor the KardiaBand currently works with all all Apple Watches except the original one.

The Apple TIRNF per Apple:

is available for Apple Watch Series 1 and later and requires iPhone 5s or later on iOS 12.1.1 in the US, Puerto Rico, Guam and US Virgin Islands. The irregular rhythm notification feature does not detect a heart attack, blood clots, a stroke or other heart-related conditions including high blood pressure, congestive heart failure, high cholesterol or other forms of arrhythmia.

An Early Look At AliveCor’s Amazing KardiaMobile 6L: Accurate 6 Lead ECG On Your Smartphone

The skeptical cardiologist has been evaluating a demo version of AliveCor’s new KardiaMobile 6L.

I have been a huge advocate of Kardia’s single lead ECG and use it with great success in dozens of my afib patients. I’ve written about how this personal ECG monitoring empowers patients and providers and is a crucial component of the enlightened medical management of afib.

In less than a month AliveCor plans to release its KardiaMobile 6L which will provide 6 ECG leads  using a smartphone based mobile ECG system that is similar to the Kardia single lead system.

AliveCor’s website proclaims “This is your heart x 6.”

 

 

 

I was fortunate enough to obtain a demo version of the 6L and have been evaluating it.

My  first impressions are that this is a remarkable step forward in the technology of personal ECG monitoring. I’m not sure if I would call it “your heart x 6” but I feel the ability to view six high quality leads compared to one is definitely going to add to the diagnostic capabilities of the Kardia device.

Kardia 6L Setup And Hardware

The 6L is similar in design and function to the single lead device.

I’m including this cool spinning video (from the AliveCor website) which makes it appear, slick, stylish and  futuristic

Once paired to the Kardia smartphone app (available for iOS or Android smartphones for free) it communicates with the smartphone  using BLE to create ECG tracings.

Like the single lead Kardia the 6L has two sensors on top for left and right hand contact. But in addition, there is a third on the bottom which can be put on a left knee or ankle.

The combination of these sensors and contact points yield the 6 classic frontal leads of a full 12 lead ECG: leads I, II, III, aVL, aVR, and aVF. This is accomplished, AliveCor points out “without messy gels and wires.

I found that using the device was simple and strait-forward and we  were able to get high quality tracings with minimal difficulty within a minute of starting the process in all the patients we tried it on.

The  Diagnostic Power Of Six Leads

Below is a tracing on a patient with known atrial fibrillation. The  algorithm correctly diagnoses it. With 6 different views of the electrical activity of the atrium I (and the Kardia algorithm)  have a better chance of determining if p waves are present, thereby presumably  increasing the accuracy of rhythm determination

Depending on the electrical vector of the left and right atria, the best lead to visualize p waves varies from patient to patient, thus having 6 to choose from should improve our ability to differentiate sinus rhythm from afib.

In the example below, the Kardia 6L very accurately registered the left axis deviation and left anterior fascicular block that we also noted on this patient’s 12 lead ECG. This 6L capability, determining the axis of the heart in the frontal plane,  will further add to the useful information Kardia provides.

 

For a good summary of axis determination and what abnormal axes tells us see here.

The History of ECG Leads

When I began my cardiology training the 12-lead ECG was  standard but it has not always been that way. I took this timeline figure from a nice review of the history of the ECG

 

 

Einthoven’s first 3 lead EKG  in 1901 was enormous.

Old string galvanometer electrocardiograph showing the big machine with the patient rinsing his extremities in the cylindrical electrodes filled with electrolyte solution.
 It is mind-boggling to consider that we can now record  6 ECG leads with a smartphone and a device the size of a stick of gum

For the first 30 years of the ECG era cardiologists only had 3 ECG leads to provide information on cardiac pathology.  Here’s a figure from a state of the art paper in 1924 on “coronary thrombosis” (which we now term a myocardial infarction) showing changes diagnostic of an “attack” and subsequent atrial fibrillation

In the 1930s  the 6 precordial leads were developed providing more information on electrical activity in the horizontal axis of the heart. The development of the augmented leads (aVr, aVL, aVF) in 1942  filled in the gaps of the frontal plane and the combination of all of these 12 leads was sanctified by the AHA in 1954.


I’ll write a more detailed analysis of the Kardia 6L after spending more time using it in patient care.

Specifically I’ll be analyzing (and looking for published data relative to):

-the relative accuracy of the 6L versus the single lead Kardia for afib determination (which, at this point would be the major reason for current Kardia users to upgrade.)

-the utility of the 6L for determination of cardiac axis and electrical intervals in comparison to the standard 12 lead ECG,  especially in patients on anti-arrhythmic drugs

For now, this latest output from the meticulous and thoughtful folks at AliveCor has knocked my socks off!

Stockingfreely Yours,

-ACP

N.B. If one uses the single lead kardia device in the traditional manner (left hand and right hand on the sensors) one is recording ECG lead I. However, if you put your right hand on the right sensor and touch the left sensor to your left leg you are now recording ECG lead II and if to the right leg, ECG lead III.

I describe this in detail here. For certain individuals the lead II recordings are much better than lead I and reduce the prevalence of “unclassified” recordings.

My feeling is that by automatically including the leg (and leads II and III) the 6L will intrinsically provide high voltage leads for review and analysis, thereby improving the ability to accurately classify rhythm.

And (totally unrelated to the 6L discussion) one can also record precordial ECG leads by putting the device on the chest thus theoretically completing the full 12 leads of the standard ECG.


Please also note that I have no financial or consulting ties to AliveCor.  I’m just a big fan of their products.

A Guide To Using Apple Watch and Kardia ECG devices-What They Can and Can’t Do

Many patients (and perhaps physicians) are confused as to how best to utilize personal ECG devices. I received this question illustrating such confusion from a reader recently:

I first came across your website a year ago during persistent angina attacks, and returning now due to increasing episodes of symptoms akin to Afib. I bought a Kardia 2 yrs ago for the angina episodes, and looking to buy the Apple Series 4 for the Afib, as I want to try a wearable for more constant monitoring. What I would greatly appreciate if you had a basic guide for both the Kardia & Apple devices, specifically when and how to best employ them for unstable angina and detecting undiagnosed Afib. As in, what can I as a patient provide to you as a doctor for diagnosis in advance of a formal visit. I’m a US Iraq vet medically retired in the UK, and most of my concerns get dismissed out of hand as “anxiety”, not sure why they thought a stent would cure my anxiety though  

Personal, Wearable ECG Devices Won’t Diagnose Angina (or Heart Attacks)

First. please understand that none of these devices have any significant role in the management of angina. Angina, which is chest/arm/jaw discomfort due to a poor blood supply to the heart muscle cannot be reliably diagnosed by the single lead ECG recording provided by the Apple Watch, the Kardia Band or the Kardia mobile ECG device. Even a medical-grade 12 lead ECG doesn’t reliably diagnose angina and we rely on a constellation of factors from the patient’s history to advanced testing to determine how best to manage and diagnose angina.

Second, as you are having episodes “akin to Afib”, all of these devices can be helpful in determining what your cardiac rhythm is at the time of the episodes if they last long enough for you to make an ECG recording.

The single lead ECG recording you can make from the Apple Watch, the Kardia Band and from the Kardia mobile device can very reliably tell us what the cardiac rhythm was when you were feeling symptoms.

The algorithms of these devices do a good job of determining if the rhythm Is atrial fibrillation. Also, if the rhythm is totally normal they are good at determining normality.

However, sometimes extra or premature beats confuse the algorithms resulting in an unclassified tracing and (rarely) an inaccurate declaration of afib

These tracings can be reviewed by a competent cardiologist to sort out what the rhythm really is.

In all of these cases, having an actual recording of the cardiac rhythm at the time of symptoms is immensely helpful to your doctor or cardiologist in determining what is causing your problems.

My recommendation, therefore, would be to make several recordings at the time of your symptoms. Print them out and carefully label the print-out with exactly what you were feeling when it was recorded and present these to the doctor who will be reviewing your case.

As I’ve mentioned in previous posts (see here), my patients’ use of Kardia with the KardiaPro online service has in many cases taken the place of expensive and inconvenient long term monitoring devices.

Case Example-Diagnosing Rare And Brief Attacks Of Atrial Fibrillation

I recently saw a patient who I think perfectly demonstrates how useful these devices can be for clarifying what is causing intermittent episodes of palpitations-irregular, pounding, or racing heart beats.

She was lying on a sofa one day when she suddenly noted her heart “pumping fast” and with irregularity. The symptoms last for about an hour. She had noticed this occurred about once a year occurring out of the blue.

Her PCP ordered a long term monitor, a stress test and an echocardiogram.

The monitor showed some brief episodes of what I would term atrial tachycardia but not atrial fibrillation but the patient did not experience one of her once per year hour long episodes of racing heart during the recording. Thus, we had not yet solved the mystery of the prolonged bouts of racing heart.

She was referred to me for evaluation and I recommended she purchase an Alivecor device and sign up for the KardiaPro service which allows me to view all of her recordings online. The combination of the device plus one year of the KardiaPro service costs $120.

She purchased the device and made some occasional recordings when she felt fine and we documented that these were identified as normal by Kardia. For months nothing else happened.

Then one day in April she had her typical prolonged symptom of a racing heart and she made the recording below (She was actually away from home but had the Kardia device with her.)

When she called the office I logged into my KardiaPro account and pulled up her recordings and lo and behold the Kardia device was correct and she was in atrial fibrillation at a rate of 113 BPM.

With the puzzle of her palpitations solved we could now address proper treatment.

Continuous Monitoring for Abnormal Rhythms

Finally, let’s discuss the wearables ability to serve as a monitor and alert a patient when they are in an abnormal rhythm but free of any symptoms.

My reader’s intent was to acquire a device for “constant monitoring”:

I’m looking to buy the Apple Series 4 for the Afib, as I want to try a wearable for more constant monitoring.

This capability is theoretically available with Apple Watch 4’s ECG and with the Kardia Band (using SmartRhythm) which works with Apple Watch Series 1-3.

However, I have not been impressed with Apple Watch’s accuracy in this area (see here and here) and would not at this point rely solely on any device to reliably alert patients to silent or asymptomatic atrial fibrillation.

In theory, all wearables that track heart rate and alert the wearer if the resting heart rates goes above 100 BPM have the capability of detecting atrial fibrillation. If you receive an alert of high HR from a non ECG-capable wearable you can then record an ECG with the Kardia mobile ECG to see if it really is atrial fibrillation.

At 99$, the Kardia is the most cost-effective way of confirming atrial fibrillation for consumers.

I hope this post adds some clarity to the often confusing field of personal and wearable ECG devices.

Electroanatomically Yours,

-ACP