Why is simply reading a blood pressure (BP) measurement on a sphygmomanometer so important? The answer is that measuring your blood pressure provides information about how your circulatory system is functioning. A high BP reading means your heart is working harder to pump blood throughout your body. This extra work can lead to a “weaker” heart muscle and potential damage to target organs. The arterial system “suffers” in a way when your blood pressure is high. This happens because the arterial walls are subjected to greater pressure from the blood, causing them to become stiffer and narrower, which increases the risk of stroke, kidney failure, and cardiovascular disease.
Classic mercury sphygmomanometer (analog)
BLOOD PRESSURE MEASUREMENTS
- Blood Pressure Measurement Using a Mercury Sphygmomanometer (Analog)
Although the use of the traditional mercury sphygmomanometer is gradually being phased out, they are still available on the market, and quite a few people still use them. A cuff is wrapped around the arm (usually the left arm), the pump (Poir) to inflate the cuff, and a stethoscope to listen to the sounds of the brachial artery.
When the pressure inside the cuff is higher than the pressure exerted by the heart when it contracts (systolic pressure), the cuff compresses the brachial artery, causing it to close. Blood flow stops, so no sound is heard through the stethoscope.
As the air is released from the cuff, blood continues to flow through the artery, producing a sound. At that moment, the systolic blood pressure (“high”) is recorded. As soon as the cuff pressure drops below the pressure exerted during the resting phase between two heartbeats, the sound disappears and the diastolic pressure (“low”) is recorded.
- Measuring Blood Pressure with an Electronic Sphygmomanometer
Electronic automatic blood pressure monitors are much easier to use. They are used similarly to an upper-arm cuff, but the measurement is taken simply by pressing a button. It’s important to note that in cases of arrhythmia (e.g., atrial fibrillation), their readings may be inaccurate. Recently, algorithms have been developed to overcome this problem, and electronic blood pressure monitors are already available on the market. Furthermore, devices that measure blood pressure from the wrist or fingers are not as accurate as those that measure from the upper arm; therefore, it is recommended to avoid using them. There is an official list of digital blood pressure monitors that have passed the reliability tests of the European Society of Hypertension (ESH), which you can find here.
UNDERSTANDING PRICES
Blood pressure is measured in millimeters of mercury (mmHg) because the traditional measuring device, called a sphygmomanometer, uses a glass column filled with mercury and marked in millimeters. As the cuff inflates or deflates, the mercury level in the column changes (see image). Although mercury sphygmomanometers are still available on the market, as mentioned, newer mercury-free electronic devices now make up the majority. Nevertheless, they are calibrated to display readings in millimeters of mercury.
Systolic pressure reflects the pressure exerted on the walls of the brachial artery during the heart’s pumping phase (systole). Diastolic blood pressure represents the pressure during the resting phase between heartbeats (diastole). Hypertension is defined as a blood pressure reading in the doctor’s office of 140 mm Hg systolic or 90 mm Hg diastolic , or both, according to the latest 2018 guidelines from the European Society of Cardiology (ESC) and the European Society of Hypertension (ESH). However, based on the new guidelines, treatment for hypertension may also be initiated at lower levels, depending on each patient’s medical history and risk factors.
To measure blood pressure accurately, two or more readings should be taken after the person being tested has been at rest for at least five minutes. Guidelines emphasize the importance of treating hypertension sooner rather than later to prevent heart disease, stroke, and kidney damage. The appropriate strategy is tailored to each patient and includes a combination of diet, exercise, stress reduction, and medication. The table below shows the classification of hypertension based on blood pressure readings (ESC/ESH 2018).
BLOOD PRESSURE TARGETS DURING TREATMENT, BY AGE GROUP AND COMORBIDITIES
Because hypertension and diabetes affect the same organs, drug therapy generally begins at an earlier stage in people with diabetes. For people with diabetes, chronic kidney disease, cardiovascular disease, a history of ischemic stroke, and those over 65 years of age, the target systolic blood pressure is set at 130 to 139 mmHg and the diastolic blood pressure at 70–79 mmHg.
The initiation of antihypertensive treatment (lifestyle modifications and medications) should be considered not only for blood pressure readings ≥140/90 mmHg but also for high-normal blood pressure levels (130–139/85–89 mmHg), provided that patients have a history of established cardiovascular disease (e.g., coronary artery disease).
In addition, low-to-intermediate-risk patients with stage 1 hypertension (140–159/90–99 mmHg) and no subclinical target organ damage should receive medication if lifestyle interventions fail to control mild hypertension over a short period of 3–6 months. This recommendation also applies to patients aged 65–80 (but not older than 80), provided that these elderly patients are in good physical condition and the treatment is well tolerated.
The primary goal of antihypertensive therapy is to lower blood pressure to <140/90 mmHg in all patients; however, if the treatment is well tolerated (without side effects), then for most patients the target should be lowered to <130/80 mmHg.
Especially in patients aged <65 έτη ο στόχος της συστολικής αρτηριακής πίεσης πρέπει να είναι εξαρχής στο διάστημα τιμών 120-129 mmHg. Αντιθέτως, σε ασθενείς ηλικίας 65-80 ετών ο στόχος της συστολικής αρτηριακής πίεσης πρέπει να είναι λιγότερο επιθετικός με τιμές 130-139 mmHg. Για τους υπέργηρους (>80 years), the latter goal may be pursued as long as it is well tolerated.
In conclusion, the guidelines recommend the following parameters for the management and treatment of hypertension:
- lower targets (<130/80 mmHg) but not for everyone
- age (<65, 65-80, >80 years)
- side effects (i.e., whether the treatment is well tolerated by the patient)