Blood Pressure

Updated

I became interested in hypertension in 2011 after recovering from a stroke attributed to hypertension. This post was published in 2023 (as part of a longer post), edited and republished in 2025 and 2026.

Pressure

The noises of the heartbeat, the flow of blood through blood vessels, and the detectable pulse in blood vessels have been known for a very long time. Medical science credits the idea that blood circulated through the body by vessels from and to the heart to William Harvey, in 1628. This theory was a better idea than the idea of “humours” postulated by classical and medieval Greek, Roman, Arabic, and middle Eastern writers.

The idea that the heart is a pump and that blood flows in arteries and veins implies that there is pressure in the arteries and veins. Humans may faint or become dizzy but do not have a sense to directly detect when their blood pressure is not normal or healthy.

Blood pressure measurement is a medical technology are used to investigate the operation of the human circulatory system. Measurement of pressure was identified and tested at the end of the 19th century. The Wikipedia entry for the Sphygnomanometer summarizes the invention and development of devices to measure blood pressure:

  • the invention of the mercury column devices (1881), analagous to Torricelli’s 17th century mercury barometer,
  • the invention of the inflatable brachial cuff (1896),
  • the medical research by Korotkov, and the existence of Korotkoff sounds,
  • the adoption by the medical profession of blood pressure measurement devices with inflatable cuffs, and
  • the ausculatory method of determining blood pressure.

The Wikipedia entry for Blood Pressure noted, as of late 2023, “Blood pressure is one of the vital signs … that healthcare professionals use in evaluating a patient’s health.” Systolic pressure is the maximum pressure during one heartbeat. Diastolic pressure is the minimum pressure between two heartbeats. The units of measurement are millimeters of mercury (abbreviated mmHg), derived from the original mercury column sphygnomanometer.

According to advocacy groups, including the American Heart Association (“AHA”) and medical charities, and members of the health care communities, the normal blood pressure of a “normal healthy” adult is 120 mmHg systolic and 80 mmHg diastolic, written as 120/80 (spoken as “120 over 80”).

The AHA’s online pamphlet Understanding Blood Pressure Readings classifies of 5 bands of BP readings. Hypertension can be described(by the AHA stage 2, above) as a medical condition in which the blood pressure in the arteries is persistently elevated – systolic blood pressure is elevated (>140 mmHg) with a normal diastolic blood pressure. Isolated systolic hypertension may present a health concern. Where elevated readings (>140/>90) appear twice, a medical doctor can diagnose hypertension.

Wikipedia, referring to modern medical consensus, does not state that 120/80 is a univeral “normal” pressure, and instead places normal in a range:

Blood pressure is classified by two measurements, the systolic and diastolic pressures, which are the maximum and minimum pressures, respectively. For most adults, normal blood pressure at rest is within the range of 100–130 millimeters mercury (mmHg) systolic and 60–80 mmHg diastolic. For most adults, high blood pressure is present if the resting blood pressure is persistently at or above 130/80 or 140/90 mmHg. … Ambulatory blood pressure monitoring over a 24-hour period appears more accurate than office-based blood pressure measurement.

Wikipedia, September 2022, Hypertension

Blood pressure is variable and average pressure is higher than 120/80:

“… the average blood pressure, age standardized, since 1975 to the present, at approx. 127/79 in men and 122/77 in women, although these average data mask significantly diverging regional trends.”

… in many older people, systolic blood pressure often exceeds the normal adult range”.

Wikipedia, September 2022, Blood Pressure

Blood pressure is affected by physiological, environmental and psychological factors, and fluctuates rapidly:

Blood pressure fluctuates from minute to minute and normally shows a circadian rhythm over a 24-hour period, with highest readings in the early morning and evenings and lowest readings at night. Loss of the normal fall in blood pressure at night is associated with a greater future risk of cardiovascular disease and there is evidence that night-time blood pressure is a stronger predictor of cardiovascular events than day-time blood pressure. Blood pressure varies over longer time periods (months to years) and this variability predicts adverse outcomes. Blood pressure also changes in response to temperature, noise, emotional stress, consumption of food or liquid, dietary factors, physical activity, changes in posture (such as standing-up), drugs, and disease. The variability in blood pressure and the better predictive value of ambulatory blood pressure measurements has led some authorities, such as the National Institute for Health and Care Excellence (NICE) in the UK, to advocate for the use of ambulatory blood pressure as the preferred method for diagnosis of hypertension

Wikipedia, September 2022, Blood Pressure

Hypertension is defined:

Hypertension … is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high blood pressure, however, is a major risk factor for stroke, coronary artery disease, heart failure, atrial fibrillation, peripheral arterial disease, vision loss, chronic kidney disease, and dementia. Hypertension is a major cause of premature death worldwide.

High blood pressure is classified as primary (essential) hypertension or secondary hypertension. About 90–95% of cases are primary, defined as high blood pressure due to nonspecific lifestyle and genetic factors. Lifestyle factors that increase the risk include excess salt in the diet, excess body weight, smoking, and alcohol use. The remaining 5–10% of cases are categorized as secondary high blood pressure, defined as high blood pressure due to an identifiable cause, such as chronic kidney disease, narrowing of the kidney arteries, an endocrine disorder, or the use of birth control pills.

Wikipedia, September 2022, Hypertension

Health care professionals recognize 2 situations where elevated blood pressure readings do not demonstate hypertension:

Measurement

Blood Vessel Sounds

Ausculatory blood pressure measurement started after the stethoscope and the sphygnomanometer came into use in the 19th century. The ausculatory method was a manual method administered by trained professionals – medical doctors and nurses. In the 20th century medical offices, clinics and hospitals were equipped with sphygnomanometers. In the early attempts to measure blood pressure, the experimenters used mercury column devces. like early barometers. For much of the 20th, sphygomanomers were predominantly calibrated to the ambient air pressure for proper use. The steps of the process:

  • inflating the cuff while listening to the pulse in the artery with a stethoscope and stopping when the beating was no longer audible,
  • recording the highest pressure in the cuff as the systolic pressure,
  • releasing pressure gradually, and
  • recording the lower pressure in the cuff when the beat resumed as the diastolic pressure.

The ausculatory method was/is a “non-invasive” method to measure blood pressure by measuring the air pressure in an airtight bladder in a cuff. A cuff is wide enough to apply pressure without bruising or injury to the limb, and applied above the elbow. The bladder and the cuff are inflated with ambient air. The flow of blood in a major artery – usually the brachial artery in an upper arm – has been been restricted with cuff device. The air pressure in the cuff is the measure of blood pressure.

Vibrations

The oscillometric method is non-invasive and measures the pressure in a cuff .Oscillometric monitors work by detecting and counting oscillations, caused by the pulsing of blood though an artery while the pressure in the cuff is used to measure blood pressure. Oscillations in the circulatory system were noted in medical literature as early as 1876. The oscillometric method is dependent on the development of transducers and monitors by the medical electronics industry.

The idea of using air in a hose to trigger a switch had been used commercially to design devices with pressure switches that could monitor traffic in the 20th century. Automobile service stations used hoses and bells to alert staff that vehicle was approaching the gas pumps. Such devices are still on the market in the early 21st century to monitor entry to some properties.

The oscillometric method is used in electrically powered automated devices that inflate the cuff, detect when blood flow through the limb has paused, take readings, release the cuff, record and display blood pressure and pulse. It is analogous to a health care worker’s using a stethoscope and an aneroid sphygnomanometer, but it is different. There a number of ways of designing electriconic pressure measurement instruments.

The first commercial oscillometric blood pressure monitor was patented in the USA in 1976. This kind of monitor could detect the oscillations in the patient’s circulatory system and the pressure applied by the cuff when the oscillations of the artery in the limb to which the cuff was applied had stopped. The authors of a paper in the Journal of Human Hypertension, (available in Springer Nature‘s unlocked service) explains how oscillometric devices work:

… With every arterial pulse wave there is a small rise and fall in the volume of the limb, which in turn causes an increase and then a decrease in the pressure within the encircling cuff, which can be detected using a solid-state transducer. When the cuff encircling a limb is inflated with [a] electronic pump … the rising pressure in the cuff eventually stops arterial blood flowing into the underlying limb and pulsation ceases. This is detected by the machine which continues to inflate the cuff for a second or two more to ensure that the limb flow has stopped completely. At this point, inflation stops, and a valve opens allowing the pressure in the cuff to reduce slowly … The pressure within the cuff is monitored carefully by the machine. At first it only detects the pulseless reduction in pressure. As the pressure in the cuff falls to below the pressure of the peak of the arterial pulse, the machine begins to detect a small pressure wave which reflects the difference between the pressure in the cuff and that in the artery. With further cuff deflation these pressure differences become greater until the cuff begins to fall away from the limb and less of the volume pulsation is detected. The machine therefore records within it a series of pulse waves, which are initially flat, then very slight, then increase to a peak and then diminish until they are hardly detected.

….

Automated oscillometric machines differ with respect to their algorithms, transducers, inflation and deflation rates, cuff sizes and materials, all of which may affect the estimation of BP. These may result in significant differences in estimations of systolic and diastolic BP compared with auscultatory readings in the same patient. Some machines may be accurate in one subject group but not necessarily in others e.g. in obese or pregnant subjects.

Phillip Lewis on behalf of the British and Irish Hypertension Society’s Blood Pressure Measurement Working Party “Oscillometric measurement of blood pressure: a simplified explanation. A technical note …” , J Hum Hypertens 33, 349–351 (2019)

Wikipedia explains, more generally:

Digital meters employ oscillometric measurements and electronic calculations rather than auscultation. They may use manual or automatic inflation, but both types are electronic, easy to operate without training, and can be used in noisy environments. They calculate systolic and diastolic pressures by oscillometric detection, employing either deformable membranes that are measured using differential capacitance, or differential piezoresistance, and they include a microprocessor. They estimate mean arterial blood pressure and measure pulse rate; while systolic and diastolic pressures are obtained less accurately than with manual meters, and calibration is also a concern. Digital oscillometric monitors may not be advisable for some patients, such as those with arteriosclerosis, arrhythmia, preeclampsia, pulsus alternans, and pulsus paradoxus, as their calculations may not be correct for these conditions, and in these cases, an analog sphygmomanometer is preferable when used by a trained person.

https://en.wikipedia.org/wiki/Sphygmomanometer#Digital

Many institutions (e.g. hospitals, medical clinics and medical offices), use automated oscillometric devices. Many institutions, particularly medical offices, still have aneroid sphygnomanometers that display pressure on a dial. Digital oscillometric devices were marketed to, and purchased by institutions Automated oscillometric devices have become the standard, and are less time consuming for health care providers. Single reading devices have been the standard. Devices capable of taking 3 consecutive readings and providing an average reading have been acquired by some institutions. The devices built to professional standards are accepted as relatively accurate and reliable by medical professionals. Devices built for hospitals and clinics may load information into networked health records.

Some oscillometric devices owned by pharmacists are available for public use. Many pharmacies in Victoria BC and across Canada have them. A special type of automated oscillometric meter for ambulatory measurement. The patient is fitted with a cuff at attached to an elecric monitor in a clinic. The monitor inflated the cuff at intervals and takes readings over a long period.

Many manufacturers market oscillometric, automated monitors for home use.

Resources

Wikipedia entries provide information on the science and the medical views of several relevant subjects:

The American Heart Association (AHA):

Hypertension Canada:

Home Use Monitors

What, Why

Home use devices are specialized oscillometric devices that share some of technology of the devices manufactured for medical establishments and professionals. They have “chips” and “boards” to start routines when buttons are pushed, but generally are not capable of running programs like home computers and smart phones. They do not have network capability to connect to routers and to other network devices (except a few monitors that have Bluetooth radios and connect to smartphones running an app.).

The main purpose of using a home monitor is to allow people detect high blood pressure and hypertension without a medical examination. Home measurement is not accepted by medical professionals as a basis for medical diagnosis. Home measurement avoids readings affected (inflated) by white coat syndrome. However the opportunity for prolonged rest can make home readings seem lower than professional measurements, and using a home monitor accurately requires practice and effort. Home devices provide some evidence of white coat or other circumstances affecting office and clinic reading. Home use devices deliver acceptably accurate readings, if:

  • the device is working and operated correctly,
  • the cuff is applied properly,
  • the patient has been inactive, is warm and comfortable and seated, sitting with the correct posture.

Doctors ask patients if they have been using home monitors but will not diagnose hypertension or provide advice or prescribe treatment with having measured blood pressure.

The use of home devices is encouraged by Hypertension Canada.

Home blood pressure monitoring (HBPM)
can be used in the diagnosis of hypertension,
and monitoring on a regular basis should be
considered for all hypertensive patients and
particularly those with:

  • Inadequately controlled hypertension
  • Diabetes mellitus
  • Chronic kidney disease
  • Suspected non-adherence
  • Demonstrated or suspected white coat effect
  • BP controlled in the office but not at home (masked hypertension)
    If white coat or masked hypertension is suggested by HBPM, it should be confirmed by repeat HBPM or ABPM before treatment decisions are made.
2020 HYPERTENSION HIGHLIGHTS Pamphlet https://hypertension.ca/wp-content/uploads/2023/05/2020-Guidelines-Highlights.pdf

The pamphlet is supported by a paper published in the professional section of Hypertension Canada’s resources, and in the journal of the Canadian Medical Association (“CMA Journal”). The paper outlines that physicians must measure blood pressure directly before diagnosing or treating hypertension.The authors write:

Because detection and management of hypertension rely on
accurate BP measurement, it is important to use a device that
has been validated and confirmed for accuracy. Validated auto-
mated oscillometric devices are preferred to auscultatory sphygmomanometers as they are easier to use, less prone to human
error and end-digit preference (i.e., where the observer rounds off the last digit), and have better reproducibility. Validation
demonstrates relative equivalency between the tested device
and rigorously performed manual auscultatory measurements.
Globally, only 10% of devices have evidence of validation for
accuracy. In Canada, 90% of BP devices sold at pharmacies are
validated compared with only 45% of BP devices sold by online
retailers. Exceptions where automated devices are inaccurate
and manual BP measurement is preferred include in patients
with persistent or high burden of arrhythmias, and populations
in which an automated device has not been validated (e.g., children and pregnant people, for whom this guideline is not intended).
Even when a validated automated device is used, the accuracy of BP measurement may be influenced by many factors. A standardized procedure with proper preparation and positioning, appropriate equipment, and multiple averaged measurements reduces variability.

Gopil et al. CMAJ 2025 May 26;197:E549-64. doi: 10.1503/cmaj.241770, https://www.cmaj.ca/content/cmaj/197/20/E549.full.pdf

The authors make assumptions about the testing of home devices and the validity of readings. The mechanism for automated devices to be validated, and the definition of a validated automated device are not clear.

Hypertension Canada has and has had a program allowing manufacturers to mark the packaging of some home devices with a check mark and the logo of Hypertension Canada. As of 2025, the mark indicated that the products was approved. At one time Hypertension Canada supported Gold and Silver marks. 1“Those with a Gold rating meet the highest and most current international standards, and those with the Silver ratings meet the highest international standards available prior to their most recent updates. (Both Gold and Silver levels are accepted as accurate)”. Hypertension Canada does not say it has tested samples of rated models. Hypertension Canada requires manufacturers seeking approval to say that they have processes that manufacture devices that meet the CSA and IEC standards, which will be noted below.

Devices from different manufacturers may read and report blood pressure and related facts differently. The differences arise from the way the devices are made and way that users operate the machines.

Basic Features, Use

Home blood pressure monitors take single readings and display readings. screen. Home use devices generally are sold as packaged sets with:

  • an operating unit which has
    • the pump that which inflates the cuff;
    • sensors that detect the pulsing artery and the pressure in the cuff;
    • control buttons and
    • a display screen;
  • a power transformer and/or several batteries;
  • a cuff; and
  • a printed manual or reference booklet

Most devices include an electric pump that inflates the cuff. Some require manual inflation with a manual inflation device (a squeezable bulb or pump) that can be operated while the person being monitored is wearing the cuff. A device with an electric pump takes about 30 seconds to inflate the cuff and deflate the cuff for a single reading.

Most devices have an LCD display (usually monochrome) that display icons and numerals. There are icons that flash as the cuff deflates and/or as the pump inflates the cuff and the cuff deflates. An icon flashes when a heartbeat or pulse is detected, according the design decisions of the manufacturer Conventionally the icon is heart shaped. When the cuff is being inflated or deflated, the pressure in the cuff changes every few seconds. When the cuff has been deflated the device displays reading as counted by the device using its algorithms. When the cuff has been is deflated and the reading is complete the device displays the reading of three parameters:

  • systolic pressure,
  • diastolic pressure, and
  • pulse (in beats per minute).

Numerals are displayed digitally. Some devices will also display:

  • an icon that the patient or the cuff has moved;
  • an icon for “irregular heartbeat” and the number of irregular beats during the monitored period,
  • an icon that the device has detected atrial fibrillation; and
  • some other error codes that are explained in a printed manual supplied by the manufacturer.

Most devices have features that remind the user that the expected or normal adult blood pressures are 120/80. These may include some or all of: graphics printed on the monitor or cuff, icons that light up when the device completes a reading, or text in the device documentation. The graphics and icons may not be appropriate for many persons, because the idea of normal is a little flexible.

A patient must install the cuff, take the reading and record the result. Manufacturers address this in the device documentation. The readings have to be recorded in some way if a person wants to remember them and communicate them to health care professional. Some write them down. Some put them electronic programs including word processor tables, spreadsheet and data base tools.

The American Heart Association’s 2025 web article Home Blood Pressure Monitoring provides a series of good practices around the use of home blood pressure monitors:

It’s important to have them make sure your home monitor is accurate and that you have the correct cuff size and fit. A cuff that is the incorrect size will cause an inaccurate blood pressure reading.

When preparing to take your blood pressure:

  • Plan ahead. Don’t smoke, drink caffeinated beverages or exercise within 30 minutes before taking your blood pressure. Empty your bladder.
  • Take multiple readings and record the results. Each time you measure, take two readings one minute apart. Record the results using a printable tracker. If your monitor has built-in memory to store your readings, take it with you to your medical appointments. Some monitors may also let you upload your readings to a secure website. 
  • Don’t take the measurement over clothes. Remove the clothing over the arm that will be used to measure blood pressure.
  • You can use either arm. Usually there is not a big difference between readings on them.
  • Be still. Allow at least five minutes of quiet rest before measurements. Don’t talk or use the phone.
  • Sit correctly. Support your arm on a flat surface and make sure it is at heart level (prop a pillow underneath your arm if needed). The middle of the cuff should be placed on the upper arm at heart level. The bottom of the cuff should be placed directly above the bend of the elbow on your bare skin, not over clothing. Check your monitor’s instructions for an illustration or have your healthcare professional show you how.
  • Measure at the same time every day. Take the readings at the same time each day. Talk with your healthcare professional about how often to take your blood pressure.

These recommendation to take multiple readings separated by at least a minute alludes to compression of the limb where the cuff has been applied and venous congestion but do not explain. It is a technical subject that I am relucant to try to explain. Manufacturers, academics and health care professional have guidelines. Many favour taking the average of multiple readings in a fairly short period of time but differ in their views on the time interval between readings. The American Heart Association guidelines (2025 web article cited above):

Each time you measure, take two readings one minute apart. Record the results …. If your monitor has built-in memory to store your readings, take it with you to your medical appointments. Some monitors may also let you upload your readings to a secure website. 

Cuffs

Cuffs are specific for a brand and model – the hoses have specific fittings for specific devices – and cannot be used with most other home monitor devices.

A cuff is a package of fabric. It might be flat. It is used after being pulled into a cylindrical shape. The exterior is made of a durable material, which holds an inflatable, airtight, interior bladder. The top of the cuff forms the exterior of the cuff, which is wrapped around a body part – usually the upper arm of an adult. The hose connecting the cuff to the device projects from a fitting on the exterior surface. The fastening device is attached to one end of the cuff also to the exterior of the cuff where the cuff overlaps when the cuff is drawn into a cylinder wrapping the limb. The inflatable cuff is the inner layer of the cuff assembly. Its outer layer has a fastener sewed into the shell. The hose fitting is on the outside so that it will be on the outside of the cuff as it is inflated.

Many home devices have flat cuffs that are wrapped around a limb. The fabric shell places enough pressure on the cuff to ensure the cuff contacts the arm. It is necessary have the cuff contacting the limb, and to close and fasten the cuff.It is not necessary to pull the cuff tight – it tightens when it is inflated.

The fastener may be a buckle. The adhesive hook and loop fastener system(commonly known as Velcro) is used in devices built in and after the late 20th century. The hooked fabric and the loop fabric are both on the outside of the cuff. A short section of hooked fabric is at the free end of the cuff. The free end may be passed through a flat D shaped metal slider and pulled back to form the cuff into a cylinder. The free and with the hooked fabric and press into the loop fabric to close the cuff and hold it in place.

Some home device cuffs have use a flexible internal plastic shell which pulls the cuff into a curve around the limb where the cuff is applied. This makes the cuff easier to fit on an arm, and easier to fasten

Some cuffs (e.g. BIOS Diagnostic Easy-Fit BD41RC) are assembled into cylinders is secured with devices that use ratcheting dials and wire. The dial is pressed and turned to lock the mechanism, tighten the cuff and hold the cuff in contact with the limb. This works like the “BOA”devices that secure some sporting footwear 2trademarked BOA systems are made or licensed by the US firm Boa Technology, Inc..

Consumer Electronics

Home monitors are medical consumer electronics. Home use devices cannot be maintained or serviced by consumers. They are sold without prescriptions in the retail sections of pharmacies or “drug stores”(in the UK “chemists”) . In Victoria, British Columbia, many such stores are part of retail store chains. The chains include London Drugs, Shoppers Drug Mart, Pharmasave, and Rexall. Chain stores and other retain drug stores acquire monitors from wholesale distributors. The devices are branded devices. The brands available include national and international brands and store brands.

There are many firms manufacturing and marketing home devices, including:

  • Omron – the Japanese firm Omron based in Mukō, a city in the Kyoto urban area in the Kyoto prefecture in Japan, manufactured in Vietnam;
  • Thermor Limited (in Canada, based in Newmarket, Ontario. Thermor was founded as Taylor Instrument Companies of Canada, founded in Toronto,. Ontario before 1939, (3not to be confused with other brands, companies or business names named “Taylor” including the modern USA firms (1) Taylor Technologies associated with maintaining swimming pools, or (2) Taylor USA, which distributes scales, thermometers and other measuring devices. Thermor uses the BIOS brand “BIOS Weather” for what seem to be precise, high quality thermometers and hygrometers. Thermor uses the BIOS brands BIOS Medical, BIOS Diagnostic for blood pressure monitors and medical electronics. Thermor also manufactures devices sold as store brands by retail chains – for instance Be Better, a store brand sold in Rexall pharmacies in Canada. The BIOS web presence of Thermor is at the BIOS Medical site. Most Thermor devices, including BIOS brand blood pressure monitors, are manufactured in China.

Options/Features

Memory

Most home use monitors have digital memory and record several readings, organized by the date and time. The device manuals and other available material do not discuss the technology used to operate the device and to make and manage records of readings.

Many devices organize the readings as taken from a specific person identified in records made on and by the device with a user number. Other data of readings includes dates and times in the system clock.

Some digital programs permit the user to calculate the average of readings in a period time. Omron series 7 and series 10 devices have a program to average the values in all readings taken within a 15 minute period.

Some professional monitors take a series of three consecutive readings, and calculate the average. The technology for this has been carried into home devices. Omron series 10 devices have the capability, called “TruRead” to be set to take a series of three consecutive readings and display the average of the three. The Omron devices allow the user to select the interval between the readings as 15, 30, 60 or 120 seconds. A triple reading with the waiting period set at 60 seconds takes about 4 minutes. BIOS makes devices with the triple reading capability, which it calls “Averaging Mode”, with a 30 second interval.

Beat parameters

Some devices measure the intervals between beats. Several devices display an “irregular” heartbeat warning icon where the monitor detects a rhythm. Irregularity can appear from the pulse rate, which can be expected to be between 60 and 100 beats per minute. It is not clear from the device what any particular manufacturer consider to be irregular, which may be stated in a manual or other producd document. The method of detecting irregularities is not normally stated in the product material. The medical term Arrythmia covers many conditions.

The warning a triggered in some Omron devices when the rhythm was 25% higher or lower than the average rhythm more than once during the monitored period. Some devices would display another icon indicating if 2 or 3 such irregular beats occurred.

The irregular heart beat icon on home devices can be triggered by movement, occur when the cuff is not attached properly, or when the user coughs or sneezes.

AFib Detection

Atrial Fibrillation is a condition diagnosed with the use of an EKG (also know as ECG (Electro-Cardi0gram). The term covers several arrythmias, including a form of tachycardia.

Omron makes a device called “Complete™ Wireless Upper Arm Blood Pressure Monitor + EKG” known by model number BP7900. It is marketed in the USA with the marketing claim that it was “developed with AliveCor, the market leader in FDA-cleared personal EKG technology, and uses an advanced new algorithm for improved detection of AFib.” The EKG feature is described as a single-lead EKG. In a professional EKG is taken on a conventional 12 lead device, “… ten electrodes are placed on the patient’s limbs and on the surface of the chest. The overall magnitude of the heart’s electrical potential is then measured from twelve different angles (“leads”) and is recorded over a period of time (usually ten seconds). In this way, the overall magnitude and direction of the heart’s electrical depolarization is captured at each moment”. Patients can be fitted with a mobile EKG known as a Holter monitor.

The promotional material for several oscillometic home monitor devices claim that those devices can detect AFib without an EKG. A web site discusses how an automated home monitor can do this:

There are two main approaches on the market in 2026… Pulse-wave analysis is the most common method; the cuff inflates, the sensor reads the tiny oscillations in … [the] artery wall, and a proprietary algorithm decides whether the rhythm looks regular or irregular. The OMRON Platinum 4a new model in 2026 sold in the USA, also known as the Omron model BP-7465… use[s] this technique …

….

When a monitor flags an irregular rhythm, it usually displays a small heart symbol with a wavy line. This does not diagnose AFib. It tells you that during this reading, the rhythm looked suspicious enough to flag. Most devices with true AFib detection will explicitly say “AFib” or show a dedicated icon. Generic “irregular heartbeat” alerts on cheaper monitors often only catch premature beats, not true atrial fibrillation.

Blood Pressure Monitors for Atrial Fibrillation in 2026, Cleve Land Heart (NB not the Cleveland Clinic)

Cleve Land Heart is source of unknown authority. It is not the famous non-profit Cleveland Clinic or the publisher of the Cleveland Clinic’s Heart Advisor newsletter. Nor is it the Jordanian entity that identifies itself on the web as clevelandheart.net

AFib detection by an algorithm on a blood pressure monitor has value, noted in the abstract of a metaanalysis of studies in 2024:

There is considerable and consistent evidence suggesting high diagnostic accuracy of AF detection algorithms implemented in automated BP monitors during routine BP measurements in and out of the office. AF diagnosis requires verification (electrocardiography) before treatment is administered.

Atrial Fibrillation Screening During Routine Automated Office, Home, and Ambulatory Blood Pressure Measurement, K. G. Kyriakoulis et al, Hypertension Volume 81, Number 7, https://doi.org/10.1161/HYPERTENSIONAHA.123.22563
Bluetooth

Some devices -e.g. the Omron BP7430, BP7450 and BP7455 – have a Bluetooth radio to upload data to another device with a Bluetooth radio. This features may have value to some users. It is unlikely that users will be able to send readings from their mobile phone to medical professionals, who normally would not spend time going through that data or want to store it.

Some retailers advertise devices with Bluetooth as wireless. Technically this may be correct -Bluetooth is a radio. However there do not appear to be home blood pressure monitors that can connect to a WiFi router, or a computer, or to the internet.

Standards

The manufacturers assert ownership and control of their own patents, trade marks and trade secrets. There are some safety standards for electric devices.

The Canadian federal government and provincial governments do not legislate how home monitors are supposed to be built. The Canadian federal department of health has a list of approved standards, including standards for electromedical devices, a requires persons operating some facilities to hold federal licences. The standards are those of national and international agencies including the Canadian Standards Group (CSA), and the International Electrotechnical Commission (IEC). Many CSA standards are republications of IEC standards. Standard 60601-1, and amendments, addresses General requirements for basic safety and essential performance of electrical medical equipment.

Manufacturer Manuals

The manufacturers of home devices distributed in Canada provide instructions to users in manuals. The manuals are found in sealed packages with the devices and generally note available to purchasers until they have bought the device and opened the package. The publication date of the manual, if stated, may suggest the year in which a device was first mass produced and put on the market.

Manuals will contain any safety information required by law and some information about the operation and features of the device. A manufacturer may make a statement about the expected service life of the product. Omron does but other manufacturers do not.

Few manufacturers disclose the key components – the sensors, pumps, seals, switches and chips used to build the devices.

The manufacturer will say something about the process of taking a reading with a home device and the expected time required to take readings. A manual will advise taking readings in a quiet place, at the same time, keeping warm, avoiding stress and not taking readings for at least 30 minutes after bathing, consuming alcohol or caffeine, smoking or exercising. Similar advice can also be found in resources like the American Heart Association sited note above, orthe Canadian advocacy entity Hypertension Canada’s pamphlet for professionals.

Omron has consistently suggested that a person sit down and rest for at least 5 minutes before starting a reading. Omron also said in (section 3.3) its manuals for BP7430 and BP 7450 devices that there should be a period of rest of 2-3 minutes after one reading and before a second reading.

Manuals may contain implicit disclaimers about the precision of readings. The manual for the BIOS BD410, a home use device made by Thermor Limited, says: “1.2C Many questions arise when two blood pressure devices are compared in an effort to check accuracy. ….”. Monitors distributed in Canada should declare or assert a margin of error in the pressure readings under technical specifications in the manuals packed with the monitors. Examples:

BrandModelTerm
BIOSBD410static accuracy± 3 mm Hg
OmronBP7350CANaccuracy± 3 mm Hg
OmronBP7450CANaccuracy± 3 mm Hg

Some information will be disorganized or confusing. For instance the manuals of many devices address electrical interference. Examples of the text used are noted here.

The 2019 Omron “7 Series Upper Arm Blood Pressure Monitor” manual recites:

DO NOT use use this monitor in areas containing high frequency surgical equipment, magnetic resonance imaging equipment, computerized tomography scanners. This may result in incorrect operation of the monitor and/or cause an inaccurate reading.

….

During measurement, make sure that no mobile device or any other electrical device that emits electromagnetic fields is within 12 inches (30 cm) of this monitor. This may result in incorrect operation of the monitor and/or cause an inaccurate reading.

The BIOS BD410 manual recites:

“1.2B

….

Using the unit in the immediate vicinity of mobile phones, microwave appliances or other devices with strong electromagnetic fields may result in impaired functioning.”

These passages do not explain what state a mobile phone should be in or which services and device radios enabled (airplane mode, cellular radio, wifi radio, bluetooth radio on or off, or totally off). They do not mention proximity to a wifi router. They do not discuss which appliances have electromagnetic fields. Does a dehumidifier (a device with cooling coils like a refrigerator or air conditioner) have an electromagnetic field?

Consumerism and Markets

Manufacturers design new features and products, but follow the business models of their industry. Certain components are made the same way for years, with incremental changes. The manufacturers do not have model years, but they will market devices as instance or models of their “brand”. They only make a limited number of models available in several markets.

There can be confusion between models made during manufacturing, related to a marketing strategies. In 2019 Omron began producing an upper arm blood pressure monitor marketed in Canada in the 2020s. The Omron monitor known by the model number BP7430CAN and the phrase “Series 7” in the model name was sold in Canadian retail stores for several years. (The letters “CAN” in the number indicated a model for the Canadian market with labels and manual that were in English and French.) By 2021 Omron had developed another monitor that was on the market in Canadian retail stores in 2026 known by the model numbers BP7450CAN and BP7455CAN. Both had the phrase “Series 10” in the model name. Both resembled the BP7430 and were sold with same model cuff. These devices were similiar to the BP7430CAN, with changes:

  • The display had white lettering on a black or dark grey background;
  • A memory function that had not been in the BP7430- that calculated the average of readings taken within 10 minute of each other;
  • A “Tru-Read” mode of measurement – the device could be set to take three measurements in succession in a few minutes and calculate the average.

The Tru-Read feature is similar to a feature in some machines used in hospitals and clinics and a few other home use devices marketed by Omron’s competitors.

By autumn 2026 Omron had another model sold in the USA (and marketed on the Internet) BP7465, also marketed as the BP 7465 Platinum model which also had the phrase “Series 10” in the model name. The BP 7465 was marketed as detecting and warning of symptoms of Atrial Fibrillation – a condition diagnosed with the use of an Electro-Cardi0gram. In Canada Omron sold its remaining inventory of BP7450 and BP7455 devices at discounted sale prices. This illustrates the paradoxes of innovation and investment. Omron invested in innovation and decided to promote the newer technology. The BP7450 was a useful, high quality device.

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