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.
The skeptical cardiologist keeps his eyes open for new, potentially improved ways of personal mobile ECG monitoring and when I saw the following comments on an afib forum I was intrigued:
I recently started using a SonoHealth product that I find MUCH MUCH superior to Kardia..
Really? MUCH MUCH superior? The more someone utilizes all caps
to emphasize theirs points the less I tend to believe them. But, as I am on a mission to discover the truth in all things cardiologic I went to the SonoHealth website and encountered this:
The EKGraph would indeed appear to be MUCH MUCH superior to Kardia mobile ECG if the website marketing can be believed.
Like the Kardia the EKGraph offers a personal ECG monitor obtained using the fingertips and syncing to an app on your smartphone.
The EKGraph claims to have 3 lead capability, something it emphasizes in its marketing but it is only capable of displaying one lead at a time and , similar to Kardia one can obtain lead II and precordial ECG leads by putting one electrode on the leg or chest.
Also similar to Kardia, the EKGraph promises “rhythm detection.” As we shall learn, however, rhythm detection by the EKGraph cannot be trusted whereas Kardia has a wealth of published data supporting its accuracy.
Unlike the Kardia, the EKGraph does have a “bright LCD screen” which displays the ECG wave pattern and heart rate along with the heart rhythm diagnosis.
I emailed SonoHealth and they were kind enough to send me one of their ECG devices to demo. After spending some time with it I can say unequivocally that it should not be purchased or utilized by any patient who wants reliable personal mobile ECG monitoring with accurate diagnoses.
A few days later a package arrived containing the EKGraph in an Applesque box which also contiained a USB charging cable. In addition they included a carrying case and a tube of ECG gel.
Working With The SonoHealth APP
To make a recording one puts the metal strip on the left side of the device on hand, arm or leg and the other metal strip on the right side of the device on an opposing limb or the chest.
This very happy model gives you a feel for the size of the device and the method of making a Lead I recording.
It is possible to made a decent single lead ECG tracing with this device and view the tracing on the associated smartphone app. However, the recordings are typically very noisy and full of artifact making it hard to discern the rhythm. The software appears to lack appropriate filtering.
The SonoHealth app is free but getting it registered was a problem. On the company website support area several readers have complained of the same problem over the last few months:
I am having trouble registering on the phone because when I hit the red button to register, I see the email and username fields at the top of the form, but when I click on email, the info fields jump to name, and I can’t scroll up to access those two fields. I then get a notification that those two fields are required to register. Any suggestions?
There is no response to this issue posted 3 months ago from the company.
Syncing with the app via Blutooth is straightforward. Pressing the sync button transfers all new tracings to the app where they can be reviewed.
Tracings can be emailed or printed.
The major problem with the EKGraph is that its ability to diagnose rhythm is very limited. This device has no published data verifying the accuracy of its rhythm diagnoses whereas the Apple Watch 4 and Kardia ECG devices do. It it is not approved by the FDA.
I used the device on my self and despite identical rhythms the EKGraph called one “tachycardia” and the other “bradycardia.”
I tried using the SonoHealth on patients in my office who were in normal sinus rhythm and received wild, seemingly random diagnoses.
Whatever algorithm the device is using to diagnose rhythm is clearly not making allowances for poor quality recordings.
This patient is in NSR but the EKGraph calls it “tachycardia, VPB bigeminy” mistaking the artifact between the normal QRS beats and ventricular ectopic beats.
Multiple Sketchy Companies Utilizing Similar Hardware
I have noted other mobile ECG device with a remarkably similar appearance to the EKGraph. A search on Amazon yields AliveCor’s devices and the SonoHealth Ekgraph . The Amazon comparison page shows 3 additional EKGraph identical-appearing devices seemingly from 3 different sketchy companies all priced at $79.
A consumer asked SonoHealth about the identical external appearance of SonoHealth’s and EMAY’s devices and the company’s response was::
As a small new company making a new design for the outside shell didn’t seem viable. A mold from scratch costs anywhere from $65,000-$85,000. So our manufacturer allowed us to use their current mold to make the EKGraph.
So even though the outside is similar the software side is totally different. We have new and improved software. There’s also our own SonoHealth app that we developed from scratch.
SonoHealth is a USA company that provides excellent customer support.
I would disagree with SonoHealth’s assessment-there is nothing to suggest their software is either new or improved or even accurate.
The app that they developed from scratch is clunky and difficult to use.
Ratings and Online Presence of SonoHealth
SonoHealth posts on its website alleged reviews of EKGraph. They are uniformly positive. It’s hard to find anything that isn’t 5/5 stars. Apparently, all the problems I found with the product are unique to me.
However, these reviews should be taken with a grain of salt. A few weeks after acquiring my SonoHealth EKGraph I received an email from the company offering a gift card if I followed their precise instructions in writing a review:
TERMS: In order to receive the $10 giftcard reward you MUST write both a Companyand a Product review. We will send each reviewer the egiftcard to the email that they provided when leaving the review. (For verification purposes, the email you enter when leaving the review must match the email associated with your order.)
This manipulation of the review process is shady and calls into question the validity of any review on the company website or Amazon.
Let The (Mobile ECG) Buyer Beware
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.
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.
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.
The skeptical cardiologist has become more selective with regard to who he will accept as a new patient. In practical terms this means I now call patients who want to see me and discuss with them why they want to see me, how they were referred or heard about me, and what their expectations are.
This might seem a little odd but turns out to be an excellent way for me to meet and smooth entrance for these newbies into my practice and gather important records and recordings prior to the first visit.
Recently, when I asked one of these potential patients why they had sought me as their cardiologist, the wife told me that through her internet research she had gleaned that I was a “Keto-friendly Cardiologist.”
Given that I have challenged conventional dogma on the dangers of dietary saturated fat and cholesterol and have written about ketosis (see here and here) a few times on this blog and defended Dr. Atkins I do actually consider myself “keto-friendly”. However my prospective patient’s wife was not aware of the skeptical cardiologist as a blog writer.
How or why I was identified as Keto-friendly cardiologist was not clear.
I realized I needed to make it perfectly clear. It is now time to come out of the keto closet.
I am a “Keto-friendly cardiologist”!
I have dozens of patients who have been very successful using very low carb/high fat diets to help them lose weight and gain control of their diabetes and hypertension.
I don’t poo poo low carb high fat diets and I think they are vey compatible with a heart-healthy existence.
In fact, lately I’ve gone back to dabbling with a Keto Diet myself.
To aid me in the dabbling I have found a device called Keyto to be the key to success and understanding of my ketosis.
Keyto: Breath Sensor for Ketosis and Weight Loss
When I went back to dabbling with ketosis in early 2019 I was using the Keto-Mojo finger prick device to measure my blood levels of beta hydroxybutyrate. I liked the precision this offered compared to urine dip sticks but grew to dislike the need to prick my finger and create blood loss.
About a month ago I ordered I discovered the keto breath sensor KEYTO and have found since then that it wonderfully simplifies the process of being on a keto diet.
Keyto costs $99 and comes in a box the size of a video cassette case.
In the box is the sensor device, four blowing mouthpieces, a very simple user manual, a AAA battery and a cute little bag for carrying the device
Ethan Weiss, MD, a highly respected preventative cardiologist and founder of Keyto includes a welcoming message for users which summarizes the mission of Keyto:
We designed the Keyto program to help you over-achieve your weight loss and health goals. With the Keyto Breath Sensor in this box, and the Keyto App on your phone, you have the key to unlocking success. You’ll be eating delicious foods, losing weight, and many users even report an increase in energy and focus
Using Keyto Is Simple and Convenient
Getting started with Keyto is very easy: download the Keyto smartphone app, log in and follow the straightforward directions for pairing the breath sensor with the app.
Once paired via Bluetooth making measurements is easy. It’s important to understand the breathing technique needed and to facilitate this I strongly recommend watching the brief explanatory video Weiss has provided. Basically, you want to use a normal breath and blow for 10 seconds so that you are near the end of expiration when the device makes its recording.
To initiate a measurement you push the plus sign on the main “Journey” screen in the app then push the on button on the sensor.
Usually, if the sensor has been turned on and the app is activated the app immediately connects to the sensor, occasionally I have had to turn the sensor off and on again to initiated the connection.
At this point the sensor begins warming up, reaching a temperature of 400 degrees Fahrenheit over a period of about 80 seconds.
The app displays the progress and offers you the option of answering some questions about how you are feeling and doing on the keto diet.
I often take my BP while this is going on. Sometimes I read the New Yorker. Frequently I listen to Radiohead (Climbing Up The Walls). It takes a while. Pay attention, though. You don’t want to miss your blowing window and have to repeat the process.
The app will give you a warning about 10 seconds prior to the time you need to blow. The graph to the right appears when it is time to blow and you can view the sensors output as it tracks the acetone it is seeing over the 10 seconds that you blow.
At the end of the blow you wait a few seconds, eagerly awaiting your score. Will you be in Ketosis?
Finally, your score is revealed. In this case I was congratulated for being in light ketosis with a fat burn of “medium high.” The highest score is an 8.
You can add notes to the record of your score
If you blow a 6 the app tells you that your fat burn is high and that you are in ketosis: “metabolizing fat like a champion.”
Accuracy of Keyto
When I first began using Keyto I checked the Keyto numbers versus the beta hydroxybutyrate (BOHB) numbers I was simultaneously getting from my Keto-Mojo meter.
I found a Keyto 3 corresponded to 0.8 BOHB, a Keyto 4 to 0.9 BOHB, and a 5 to 1.0 BOHB. That was enough to convince me that the device was accurate and useful in measuring my level of ketosis.
Given that it is so convenient compared to a finger stick I have stopped using the Keto-Mojo completely.
My observations confirm what Weiss and Ray Wu, MD, the cofounders of Keyto describe in very lucid prose here.
In extensive user testing, Keyto is directionally consistent with the more accurate commercially available blood meter. Keyto and blood β-hydroxybutyrate trend directionally the same in the majority of cases. Both go up and down in similar magnitude at different ranges of ketosis. There are some differences which are likely due to biology – the kinetics of clearance of acetone and β-hydroxybutyrate are not identical.
Some of the differences are also likely due to how we designed the Keyto program. Our primary goal was to develop a system that would give users the information they need to know i.e. if they are in ketosis, which would ultimately help promote healthy behavior change. Therefore, we chose not to report acetone concentrations in PPM or to attempt to convert PPM to blood β-hydroxybutyrate (mmol/L). The Keyto Level system was simply more effective, motivating, and fun without adding complexity and false precision.
I can make multiple measurements throughout the day without worrying about the cost or the discomfort of a finger stick. The ability to make multiple measurements means that I am getting very rapid and frequent feed back on how my dietary and lifestyle choices are effecting my level of ketosis.
Warning! Because the device is so convenient-literally you can have it with you at all times-you may find yourself blowing into it excessively. This may irritate your friends and loved ones, especially those that aren’t on a keto diet.
Keyto is Legitimate
The Keyto website has an excellent introduction to the keto diet (keto 101) and has numerous other very helpful resources for those who seek to lose weight using the diet.
In general I get a good feeling of integrity and legitimacy from every aspect of the Keyto operation.
I have a tremendous professional respect for Ethan Weiss, the cardiologist behind Keyto. He’s very active on Twitter and is typically spot on with his comments. He’s done a podcast with Peter Attia which serves as an excellent summary of atherosclerosis and coronary artery disease. He does really good basic science research involving growth hormone.
Weiss is now doing his own podcast called Best Known Method by Keyto which I highly recommend. It is not, surprisingly, focused on the keto diet or the keyto brand but interviews thought leaders in cardiology like Ron Krauss and Lisa Rosenbaum.
If you want to read more about how the Keyto breath sensor works see here. This is a very clear and concise description of the science behind the device and it is complete with references.
Ultimately, although I consider myself a keto-friendly cardiologist, I’m most interested in the diet that helps my patients achieve and sustain their goals of weight loss and better health. For many this is the keto diet.
And for those who find the keto diet is optimal for their health I will be advising them to acquire a Keyto breath sensor and check out the programs Keyto offers to support their health goals.
When it comes to self-monitoring of blood pressure the best device (assuming equivalent accuracy) is the one that patients are most likely to use.
The Omron Evolv has become that device for the skeptical cardiologist as it combines a unique one-piece design with built in read-out with a quicker, more comfortable yet highly accurate BP measurement technique.
My previous favorite BP device, the QardioArm remains a close second.
Evolv Form and Function
The Evolv is sleek and stylish in appearance and has no external tubes, wires or connectors. It runs on 4 AAA batteries.
The cuff is pre-formed and is incredibly easy to self-administer to the upper arm. Measurement is simple. Press the start button and it immediately starts inflating the cuff.
The results are displayed on an LCD screen on the cuff.
The Omron uses an oscillometric technique to measure the blood pressure as it is inflating. This “inflationary” technique has been shown to be as accurate as measuring during deflation but is much quicker. A study using the recently developed “Universal Standard Protocol” for evaluating the accuracy of BP devices showed that the Omron Evolv was highly accurate compared to gold standard sphygmomanometry.
Omron has come up with some slick marketing terms for the inflationary and pre-formed wrap aspects:
Intellisense Technology – Inflates the cuff to the ideal level for each use.
Intelli Wrap Cuff – For an easy and accurate reading
With the inflationary technique the cuff knows when to stop inflating, (hence “intellisense”) therefore, there is less tendency to go to higher pressures compared to the deflationary technique and less potential for discomfort from those higher pressures.
Evolv Communication-Sharing Results
The Evolv communicates via Bluetooth with the Omron Wellness (or Connect) smartphone app. Your BP and heart rate measurements are easily transferred to this app and can be viewed over time.
If one clicks on the little export icon at the upper right had corner of this summary screen you can “export CSV” which creates a file of BP measurements over a defined period that can then be emailed to yourself, your curious friends, or your doctor.
Another option is to export the summary report but this is a premium feature and requires payment.
Monitoring Heart Rhythm and Blood Pressure-The Omron/Kardia Pro Connection
AliveCor has partnered with Omron and the Omron Connect (or Wellness) app is essentially the Kardia app which my patients utilize to record their ECG recordings and share them with me.
With this app, therefore, patients who have the connection subscription service can utilize the Omron app to share both their ECG and BP recordings with me online. This is really quite an amazing development.
Below are recordings from one of my patients that I took from the patient screen which I view online.
The data can be viewed in various formats including this one which gives a good idea of daytime variation in BP as well as percentage recordings in goal range.
For me, this ability to rapidly view patient’s blood pressures over time in meaningful ways greatly facilitates management. If we could find a way to seamlessly import these data directly into our EMR it would an even bigger step forward.
Speaking To Your BP Cuff
I don’t use Alexa but Omron highlights how the Evolv works with Alexa:
Somehow, this doesn’t seem helpful to me but I tried asking Siri (with both my Apple Watch and iPhone) if she could give me info on my blood pressure and she failed miserably
Evolv-The Future of BP Management?
To summarize why I am so enthusiastic about this BP cuff
Portability and compactness. One piece design without tubes or wires.
Rigorously proven accuracy
Quicker and more comfortable than “deflationary” cuffs
Read-out on cuff-no separate unit or smartphone required
Communicates well with highly functional app for organizing or reporting BP measurements over time
Coordination of ECG measurements from Kardia and BP measurements on app through KardiaPro facilitates physician management of patient’s cardiovascular conditions.
N.B. In the course of researching the Omron Evolv I looked at multiple home BP monitor review websites online. Almost without exception these were worthless. I suspect many of these device review sites are funded by companies making the products. Others just aggregate information from company websites and regurgitate it without analysis. Websites with apparent consumer reviews are also suspect as I have found unscrupulous vendors are manipulating the whole review process.
Fortunately, your trusty skeptical cardiologist remains unsullied by any financial connections to corporate America. Or corporate Japan for that matter (It appears Omron has its headquarters in Kyoto, Japan). However, Omron, if you are listening perhaps you can send me for my review one of your new Complete combined BP and EKG monitoring devices!
And one final detail. I checked just now and you can purchase the Evolv at Amazon for $69. Bundles that connect you to your doctor through the cloud and get you an Evolv plus or minus the Kardia ECG device at a reduced price are available through both the Kardia and Omron websites and apps.
The skeptical cardiologist primarily makes decisions on blood pressure treatment these days based on patient self-monitoring. If high readings are obtained in the office I instruct patients to use an automatic BP cuff at home and make a measurement when they first get up and again 12 hours later. After two weeks they report the values to me.
Although I’ve been recommending self-monitoring to my patients for decades it is only recently that guidelines have endorsed the approach and good scientific studies verified its superiority. I was pleased when the 2017 ACC/AHA guidelines for High Blood Pressure made home self-monitoring of BP a IA recommendation.
And last year a very good study, the TASMNH4 was published which demonstrated the superiority of self-monitoring compared to usual care.
TASMINH4 was a parallel randomised controlled trial done in 142 general practices in the UK, and included hypertensive patients older than 35 years, with blood pressure higher than 140/90 mm Hg, who were willing to self-monitor their blood pressure. Patients were randomly assigned (1:1:1) to self-monitoring blood pressure (self-montoring group), to self-monitoring blood pressure with telemonitoring (telemonitoring group), or to usual care (clinic blood pressure; usual care group).
The home BP goal was 135/85 mm Hg, 5 mm Hg lower than the office BP goal. At one year both home self-monitoring groups had significantly lower systolic blood pressure than the usual care group.
This trial was not powered to detect cardiovascular outcomes, but the differences between the interventions and control in systolic blood pressure would be expected to result in around a 20% reduction in stroke risk and 10% reduction in coronary heart disease risk. Although not significantly different from each other at 12 months, blood pressure in the group using telemonitoring for medication titration became lower more quickly (at 6 months) than those self-monitoring alone, an effect which is likely to further reduce cardiovascular events and might improve longer term control.
Advantages of Home Self-Monitored Blood Pressure-Limitations of Office BPs
Every patient I see in my office gets a BP check. This is typically done by one of the office assistants who is “rooming” the patient using the classic method with , listening with stethoscope for Korotkov sounds. If the BP seems unexpectedly high or low I will recheck it myself.
Often the BP we record is significantly higher than what the patient has been getting at home or at other physician offices.
There are multiple factors that could be raising the office BP: mental stress from driving to the doctor or being hurried or physical stress from walking from the parking lot.
In addition, I feel that multiple assessments of out of office BP over the course of the day and different days are more likely representative of the BP that we are consistently exposed to rather than one reading in the doctor’s office.
Accuracy and technique in the doctor’s office is also an issue.
Interestingly, we have assumed that manual office BP measurement is superior to automatic but this recent paper found the opposite:
Automated office blood pressure readings, only when recorded properly with the patient sitting alone in a quiet place, are more accurate than office BP readings in routine clinical practice and are similar to awake ambulatory BP readings, with mean AOBP being devoid of any white coat effect.
A patient left a comment to that paper which is quite insightful:
I had a high blood pressure event several years ago. Since then I have monitored my BP at home, sitting with both feet flat on the floor, not eating or drinking, not speaking or moving around, on a chair with a back, and without clothes on the arm being used for the measure. My BP remains normal.
I have never had my BP taken correctly in a doctor’s office. They will do it while I am speaking with the doctor, sitting on an exam table with my legs swinging, with the monitor band over my heavy winter sweater, right after I have sat down. They do not ensure that my arm is supported or at the right height. If I recommend that I take off my sweater, or move to a chair with a back, they tell me that is not needed. I have decided to refuse such measurements. How can they possibly be monitoring my health this way?
This patient’s observations are not unique and I suspect the majority of office BPs have most if not all of the limitations she describes.
Self Monitoring Improves Patient Engagement In BP Control
I have found self-monitoring of patient’s BP to substantially enhance patient engagement in the process. Self-monitoring patients are more empowered to understand the lifestyle factors which influence their BP and make positive changes.
Blood pressures are amazingly dynamic and as patient’s gain understanding of what influences their BP they are going to be able to take control of it.
I take my BP almost daily and adjust my BP medications based on the readings. After prolonged work or exercise in heat, for example, BPs will decline to a point where I’m light headed or fatigued. Less BP med at this time is indicated. Conversely, if I’ve been overly stressed BPs increase and upward titration of medication is warranted.
With some of my most engaged and enlightened patients we perform similar titrations depending on their circumstances. Sometimes patients perform these titrations on their own and tell me about them at the next office visit.
What’s The Best Way To Communicate Home BPs?
Many of my patients provide me with a hand-written record of their BPs over two weeks. Some mail them to me, others bring them in to the office. We scan these into the EMR. I look at these and make an estimate of the average systolic blood pressure, the variation over time and the variation during the day. It’s not feasible for me or my staff to enter the numbers or precisely obtain an average.
Some patients send us the numbers through the internet-based patient portal into the EMR. This is preferable as I can view these and respond quickly and directly back to the patient with recommendations.
More and more patients are utilizing their smart phones to record and aggregate their health data and will bring them in for me to look at during an office visit. I’ve described one stylish and slick BP cuff, the QardioArm which has neither tubes nor wires and works through a smartphone app. Omron , also has multiple cuffs which communicate via BlueTooth to store data in a smartphone app.
Ideally, we would have a way for me to view those digitally recorded BPs with nicely calculated averages online and within the EMR. Unfortunately, such connectivity is not routinely available.
However, for my patients who are already monitoring their heart rhythms with a Kardia mobile ECG and are connected with me online through KardiaPro Remote I can view their BP recordings online.
I’ll discuss in detail in a subsequent post the Omron Evolv home automatic BP cuff (my current favorite) which is wireless and tubeless and connects seamlessly to KardiaPro allowing me to view both BP and heart rhythm (and weight) recordings in my patients
To me, this empowerment of patients to record, monitor and respond to their own physiologic parameters is the future of medicine.
From the 2017 ACC/AHA BP guidelines
and the proper technique for office BP measurement
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.
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!
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.
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
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.
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.
The skeptical cardiologist recently received this email from a reader:
With the new Apple Watch that’s out now, people have suggested my husband (who had a heart attack at 36) should get it since it could detect a heart attack. But I keep remembering what you said – that these devices can’t detect heart attacks and that Afib isn’t related to a heart attack most of the time – is that still the case? I don’t really know how to explain to people that it can’t do this, since absolutely everyone believes it does.
The answer is a resounding and unequivocal NO!
If we are using the term heart attack to mean what doctors call a myocardial infarction (MI) there should be no expectation that any wearable or consumer ECG product can reliably diagnose a heart attack.
The Apple Watch even in its latest incarnation and with the ECG feature and with rhythm monitoring activated is incapable of detecting a myocardial infarction.
To make this even clearer note that when you record an ECG on the Apple Watch it intermittently flashes the following warning:
Note: “Apple Watch never checks for heart attacks”
How did such this idea take root in the consciousness of so many Americans?
Perhaps this article in 9-5 Mac had something to do with it
In reality, the man received an alarm that his resting heart rate was high at night. Apparently he also was experiencing chest pain and went to an ER where a cardiac enzyme was elevated. Subsequently he underwent testing that revealed advanced coronary artery disease and he had a bypass operation.
Even if we assume all the details of this story are accurate it is absolutely not a case of Apple Watch diagnosing an MI.
A high resting heart rate is not neccessarily an indicator of an MI and most MIs are not characterized by high heart rates. We have had the technology with wearables to monitor resting heart rate for some time and no one has ever suggested this can be used to detect MI.
The rate of false alarms is so high and the rate of failure to diagnose MI so low that this is a useless measure and should not provide any patient reassurance.
The writer of this story and the editors at 9-5 Mac should be ashamed of this misinformation.
Several other news sources have needlessly muddied the water on this question including Healthline and Fox News:
In clear cut cases the Apple Watch could make the difference between life and death,” says Roger Kay, president of Endpoint Technologies Associates. Because you wear the Apple Watch at all times, it can detect an early sign of a stroke or a heart attack, and that early indication is critical, he says.
And the Healthline article on the new Apple Watch also incorrectly implies it can diagnose MI:
The device, which was unveiled last week, has an electrocardiogram (ECG) app that can detect often overlooked heart abnormalities that could lead to a heart attack.
And if you are felled by a heart problem, the fall detector built into the Apple Watch Series 4 could alert medical professionals that you need help
Fox News and Healthline should modify their published articles to correct the misinformation they have previously provided.
And it is still true that although both Apple Watch and Kardia can diagnose atrial fibrillation the vast majority of the time acute heart attacks are not associated with atrial fibrillation.
Readers, please spread the word far and wide to friends and family-Apple Watch cannot detect heart attacks!