About High Blood Pressure

The heart acts as a pump that circulates blood in the blood vessels throughout the body.

The body’s blood circulation is broadly divided into systemic circulation and pulmonary circulation.

1. Systemic circulation

Blood pumped into the aorta by contraction of the left ventricle flows through the arteries and into the capillaries of the body’s tissues,

supplying oxygen and nutrients to each tissue and receiving carbon dioxide and waste products, then returning to the right atrium through the veins.

Left ventricle → aorta → arteries → capillaries of each tissue in the body → veins → right atrium

2. Pulmonary circulation

Blood that flows from the right atrium to the right ventricle passes through the pulmonary arteries and alveolar capillaries by contraction of the right ventricle,

releasing carbon dioxide and taking in oxygen, then returns to the left atrium through the pulmonary veins.

Right ventricle → pulmonary arteries → pulmonary capillaries → pulmonary veins → left atrium

Blood pressure refers to the pressure of blood flowing through the blood vessels. Depending on the measurement site, there are various types such as arterial pressure, venous pressure, pulmonary artery pressure, and pulmonary vein pressure, but the blood pressure commonly referred to generally means the arterial pressure measured in the arm.

The unit used to record pressure is commonly mmHg, which is also used when measuring atmospheric pressure. 1 mmHg means the pressure capable of pushing a mercury column up by 1 mm, and it is read as “millimeter mercury.”

Meanwhile, because the heart’s pumping action is generated by contraction and relaxation of the heart, the arterial pressure measured in the arm rises when the left ventricle contracts and falls when it relaxes, forming a wave pattern. The pressure at the moment when it reaches its highest point due to left ventricular contraction is called “systolic blood pressure,” and the pressure at the moment when it reaches its lowest point due to left ventricular relaxation is called “diastolic blood pressure (expansion blood pressure).”

Hypertension refers to adults whose systolic blood pressure is 140 mmHg or higher or whose diastolic blood pressure is 90 mmHg or higher.

Hypertension causes various complications throughout the body, including coronary artery disease, stroke, and kidney failure, and directly threatens the patient’s life and health. However, hypertension generally has no symptoms, so it is not diagnosed until blood pressure is measured, and even when diagnosed, the absence of symptoms means people do not feel the need for treatment. In particular, statistics in Korea show that young men tend not to seek treatment even when they have hypertension. According to the results report of the 6th Korea National Health and Nutrition Examination Survey, 2nd year (2014), recently announced by the Ministry of Health and Welfare, the prevalence of hypertension among people aged 30 and older was 30.4% overall, 34.2% for men, and 26.9% for women, with men 7.3% higher than women. In the 30s, 40s, and 50s, the prevalence of hypertension was higher in men than in women, but in the 60s and those aged 70 and older, the prevalence was higher in women. In addition, the awareness rate of knowing one has hypertension was 65.9%, the treatment rate, which is the proportion of people who know they have hypertension and are receiving treatment, was 61.3%, and the rate of patients actually receiving treatment and being well controlled was 43.8% (based on prevalence), showing that problems in hypertension management still persist. For this reason, hypertension is also called the “silent killer.”

So far, I have explained hypertension.

In the next part, we will look into hypertension in more detail.

Source: Korea Disease Control and Prevention Agency National Health Information Portal