What is high blood pressure

 1 minute to understand what is High Blood Pressure 

Through the video we have a preliminary understanding of hypertension, the next in several parts we will learn more about high blood pressure.

1. Definition of High Blood Pressure

Hypertension is a clinical syndrome characterized primarily by increased arterial blood pressure (systolic and/or diastolic) in the body circulation (systolic blood pressure ≥ 140 mm Hg and diastolic blood pressure ≥ 90 mmHg), which may be accompanied by functional or organic damage to the heart, brain, kidneys, and other organs.

2. High blood pressure damage

1 Causes cardiac hypertrophy.

• A continued increase in blood pressure will lead to greater resistance when the heart pumps blood outward, and the heart will work under high pressure for a long time will lead to myocardial hypertrophy and a decrease in myocardial contractility, which will lead to heart failure.

2 Damage to blood vessels.

• The human blood vessel wall should be smooth, if long-term hypertension, will lead to thickening of the vessel wall, causing great damage to the vessel wall, so that it is easy to suffer from various cardiovascular and cerebrovascular diseases.

3 Damage to the brain.

• High blood pressure can damage the human brain, resulting in a decline in brain function, making it impossible for people to carry out normal activities. It can also lead to ischemic stroke due to narrowing of the brain arteries, which can seriously threaten a person's life.

4 Damage to the eyes.

• High blood pressure can also cause great damage to the eyes. Long-term hypertension can lead to spasms and sclerosis of the retinal arteries, which can lead to vision loss and even blindness in severe cases.

5 Causes damage to kidney function.

• The kidneys and human blood pressure have a close relationship, long-term hypertension will cause great damage to the kidneys, resulting in renal hypertension, which will also lead to kidney failure.

6 Causes peripheral artery disease.

• Elevated blood pressure can cause the arteries of the lower extremities to undergo coronary artery sclerosis at a faster rate, thus making the arteries of the lower extremities ischemic and lack nutrients or even necrosis.

3. Causes of High blood pressure 

•  Genetic factors  Approximately 60% of patients with hypertension have a family history. It is now believed to be due to polygenic inheritance, with 30% to 50% of patients with hypertension having a genetic background.
•  ntal and environmental factors  Long-term mental tension, excitement, anxiety, exposure to noise or bad visual stimulation，and other factors can also cause the occurrence of hypertension.
•  Age factors  The incidence of hypertension tends to increase with age, with a high incidence in people over 40 years old.
•  Lifestyle factors  Irrational dietary structure, such as exces sodium, low potassium diet, heavy alcohol consumption, excessive intake of saturated fatty acids can increase blood pressure. Smoking can accelerate the process of atherosclerosis, which is a risk factor for hypertension.
•  The influence of drugs  Contraceptives, hormones, anti-inflammatory，and painkillers, etc. can affect blood pressure.
• The influence of other diseases  Obesity, diabetes mellitus, sleep apnea hypoventilation syndrome, thyroid disease, renal artery stenosis, renal parenchymal damage, adrenal occupational lesions, pheochromocytoma, other neuroendocrine tumors, etc.

4. Classification of High blood pressure

High blood pressure can be divided into two categories.

1. primary hypertension

It is an independent disease with elevated blood pressure as the main clinical manifestation but the cause is not yet clear, accounting for more than 90% of all hypertensive patients.

2. Secondary hypertension

Also known as symptomatic hypertension, in this type of disease the cause is clear, hypertension is only one of the clinical manifestations of the disease, blood pressure can be temporarily or persistently elevated.

5. High blood pressure symptoms

• The symptoms of hypertension vary from person to person. 
• In the early stage, there may be no or insignificant symptoms, commonly dizziness, headache, tight neck plate, fatigue, palpitations, etc. 
• An increase in blood pressure will occur only after exertion, mental stress, or mood swings and will return to normal after rest. As the course of the disease lengthens, the blood pressure rises significantly and continuously, and various symptoms will gradually appear, it is called bradykinetic hypertension. 
• The common clinical symptoms of bradykinetic hypertension include headache, dizziness, lack of concentration, memory loss, numbness in the limbs, increased nocturia, palpitations, chest tightness, and weakness. 
• The symptoms of hypertension are related to the blood pressure level. 
• Most of the symptoms can be aggravated after stress or exertion, and blood pressure can rise rapidly after early morning activities, resulting in early morning hypertension, leading to cardiovascular and cerebrovascular events occurring mostly in the early morning.

When blood pressure suddenly rises to a certain level even severe headache, vomiting, palpitations, vertigo, and other symptoms will occur, and in serious cases, confusion and convulsions will occur, which is the acute type of hypertension and hypertensive critical illness, and will mostly occur in a short period, serious damage and lesions of the heart, brain, kidneys and other organs, such as stroke, heart attack, kidney failure, etc. There is no consistent relationship between the symptoms and the level of elevated blood pressure.

The clinical manifestation of secondary hypertension is mainly about the signs and symptoms of the primary disease, and hypertension is only one of its symptoms. The elevation of blood pressure in patients with secondary hypertension may have its characteristics, such as hypertension due to aortic constriction may be limited to the upper extremities; the increase of blood pressure due to pheochromocytoma is paroxysmal.

6. What  tests should be done after the diagnosis of hypertension？

• The basic tests that need to be done after the diagnosis of hypertension include routine blood, urine, biochemistry, electrocardiogram, and chest X-ray. 

• If there is heart damage from hypertension, echocardiography and coronary angiography are needed. 

• With neurological damage, a cerebral angiogram, CT, or MRI of the brain is needed to check for brain bleeding or brain infarction.

• If you have hypertensive nephropathy, you need to have a kidney ultrasound, and 24-hour urine protein quantification or kidney function test to see what level of damage to the kidneys is caused by hypertension. 

• Because of the long-term high tension pressure, many patients will develop hypertensive macrovascular lesions in the advanced stage of hypertension and need to have an arteriovenous ultrasound. 

• When blood pressure is high, it can also damage the eyes, so a fundus examination is needed to check the condition of the retina. 

• When hypertension is diagnosed, in addition to understanding target organ damage, it is also necessary to know if there are any specific causes of hypertension, which requires adrenal CT, adrenal hormones, renal arteriography, respiratory sleep monitoring, and genetic testing to understand if hypertension is caused by specific causes.

You can also find more information at the links below:

1 jacc.org
2 nhlbi.nih.gov
3 all photoes from pexels