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Blood pressure is the force created when blood pushes against the walls of the arteries. Each time the heart beats, it pumps blood into the largest artery in the body, called the aorta, and the arterial tree of your body. The arteries deliver oxygen and nutrients to the body’s organs and tissues. The heart beats about 60 to 100 times each minute, continuously circulating blood throughout the body. Blood pressure naturally changes during the day and cannot usually be identified based on how a person feels. It usually increases during activities, such as exercise or when a person feels excited or stressed. It becomes lower during rest or sleep. Blood pressure can also be affected by medications, changes in body position, and aging.
Accurate measurement with proper equipment is the only reliable way to determine blood pressure levels. Regular blood pressure checks help identify hypertension early. Adults should have their blood pressure checked at least every two years beginning at age 18. Some individuals may require more frequent monitoring depending on their health status. Blood pressure is measured in millimeters of mercury (mm Hg). In general, hypertension is defined as a blood pressure reading of 130/80 mm Hg or higher. Low blood pressure, known as hypotension, can cause dizziness, fainting, and injuries from falls. In severe cases, very low blood pressure can reduce blood flow to important organs and may lead to life-threatening complications such as shock.
Healthy lifestyle habits are essential for preventing and managing high blood pressure. Avoiding smoking helps protect blood vessels and reduces cardiovascular risk. Regular physical activity, such as walking or cycling, strengthens the heart and improves circulation, lowering pressure on the arteries. A balanced diet rich in fruits, vegetables, whole grains, and lean proteins, while low in salt and processed foods, plays a key role in maintaining healthy blood pressure levels. Managing stress, maintaining a healthy weight, and limiting alcohol intake further support heart health. In some cases, medications may also be necessary to effectively control blood pressure and prevent complications.
High blood pressure, also known as hypertension, is a major risk factor for cardiovascular disease. Extremely high blood pressure, sometimes called a hypertensive emergency, can become life-threatening and requires urgent medical attention. It is estimated that 1.4 billion adults aged 30–79 years worldwide had hypertension in 2024 (33% of the world population). Most people with high blood pressure do not experience noticeable symptoms, even when their readings are dangerously high. A person may have hypertension for many years without knowing it. Some individuals with very high blood pressure may experience symptoms such as headaches, shortness of breath, or nosebleeds. However, these symptoms are not specific and typically appear only when blood pressure becomes severely elevated. Blood pressure is an important indicator of overall health because abnormal levels can lead to serious health problems. for this block. Use this space for describing your block. Any text will do. Description for this block. You can use this space for describing your block.
White coat hypertension means blood pressure is high in the clinic but normal outside the clinic on home or 24-hour ambulatory monitoring. That is different from sustained “real” hypertension, which stays high in everyday life too. White coat hypertension is real as a phenomenon linked to stress/anxiety during a medical visit which can raise blood pressure, but it usually is not treatedthe same way as confirmed chronic hypertension. White coat hypertension itself is associated with higher cardiovascular risk than completely normal BP, but lower risk than sustained hypertension. In someone withsevere ischemic heart disease or severe valve disease, white coat hypertension is taken more seriously.
Non-drug interventions
In patients with suspected or diagnosed hypertension, we recommend lifestyle advice and support to enable them to make healthy lifestyle changes like regular exercise, a healthy diet, low dietary sodium intake, and reduced alcohol intake (if excessive) as these changes can reduce blood pressure. At the same time excessive consumption of coffee and other caffeine-rich products is discouraged, and importantly, we strongly recommend advice to help smokers to stop smoking (see Smoking cessation).
Anti-hypertensive drug treatment
Hypertension is commonly managed with medication alongside lifestyle measures. Treatment often requires more than one drug, and doses should be adjusted to the maximum tolerated level while supporting adherence. Drug choice may depend on factors such as age, ethnicity, patient’s comorbidities, and individual risk factors.
- ACE inhibitors (e.g., Ramipril) and ARBs (e.g., losartan) reduce activity of the renin–angiotensin system and are commonly used first line, especially in patients with diabetes or kidney disease because they help protect the kidneys.
- Calcium channel blockers (e.g., Amlodipine) relax blood vessels and are often preferred first-line in people aged 55 years or older and in patients of black African or African-Caribbean origin.
- Thiazide-like diuretics (e.g., Indapamide) help remove excess salt and water and can be used when calcium channel blockers are not tolerated or as part of combination therapy.
- Beta blockers (e.g., Bisoprolol) and alpha blockers (e.g., Doxazosin) can be added in resistant hypertension or when there are other indications such as heart disease.
- Spironolactone, a potassium-sparing diuretic, may be used in resistant hypertension when potassium levels allow.
Resistant hypertension (or malignant hypertension) is defined as the inability to regulate blood pressure using the maximum tolerated doses of three antihypertensive drugs, one of which should be a diuretic. The American Society of Hypertension states that the level of blood pressure should be below 130/80 mmHg for high-risk groups (like patients with diabetes, renal disease and proteinuria).
The prevalence of resistant hypertension is not precisely known but it appears that the proportion of resistant hypertension does not exceed 5% in the general hypertensive population. However, two large epidemiological studies from the U.S. and Spain determined that 9-12% of hypertensive patients do actually suffer from resistant hypertension.
In the middle of last century, Sympathectomy was a very popular surgical option and the only effective method of dealing with malignant hypertension. This method, however, had many serious side effects and fell out of favour with the advent of antihypertensive drugs. Today, we have developed a new surgical method for treating resistant hypertension called Renal Sympathetic Denervation (renal artery de-nervation, RDN, Ardian). This procedure is minimally invasive with excellent safety features and however the results from recent SYMPLICITY HTN-3 trial show that renal artery denervation did not prove to be effective treatment for hypertension, as initially thought.
The Renal Sympathetic Denervation works on the sympathetic nervous system. The kidneys have a dense sympathetic innervation of afferent and efferent nerves surrounding both renal arteries. Stimulation of the afferent sympathetic nerves leads to an increase in the production of the renal hormone renin, which causes water and “salt” to be retained in the body and a reduction in blood flow through the kidneys. This process results in further stimulation of efferent sympathetic renal nerves which influence the patient’s central nervous system. As a consequence, the central nervous system increases the tone of the afferent sympathetic renal nerves, creating a vicious cycle that contributes to disease development and maintenance of what we call resistant hypertension.
Sympathetic Renal Denervation is a new interventional treatment for resistant hypertension that uses a specially designed catheter (Simplicity Catheter System, Ardian, Mountain View, CA, USA). The procedure requires insertion of the special treatment catheter (Simplicity Catheter System, Ardian) into the patient’s femoral artery (groin) and then advancing it into the renal arteries of the kidneys. Through this special catheter “electricity” in the form of “heat” ablates (destroys) the overractive sympathetic nerves which surround the arteries of the kidneys (catheter-based radiofrequency ablation). This method is minimally invasive, is performed under light sedation and local anaesthetic, and requires a minimum time of 30-40 minutes in order to perform an effective denervation of both renal arteries. After the surgery, the patient is transferred to a cardiology ward for recovery. Here, the patient receives intravenous fluids and pain relief. The patient is then mobilized out of bed after six hours. The next day the patient is usually discharged home with written instructions following an evaluation by our team.
A significant portion of patients “tagged” with resistant hypertension are in fact suffering from what we call “pseudo-resistant hypertension”. It is therefore extremely important to ensure that the correct diagnosis of resistant hypertension has been made before a patient is referred for treatment with sympathetic denervation of the renal arteries. This means that the patient has undergone a careful up-titration of antihypertensive medications, with adherence to appropriate administration of medical therapy, and with exclusion of the presence of “white coat” hypertension (whereby blood pressure goes up in the presence of a health professional). We therefore recommend a 24-hour recording of blood pressure or blood pressure measurements at home for a week, before committing the patient to the treatment of renal artery denervation (RDN, Ardian).
Another very important parameter in the evaluation process is a thorough assessment of the patients’ medical treatment for concomitant administration of medications that may increase his/her blood pressure. Medications like non-steroidal anti-inflammatory drugs (pain relief drugs), either classic or cyclo-oxygenase II inhibitors, which are taken by a large population of patients and often without a prescription, can be a cause of both an increase in blood pressure and deterioration in renal function. Other major causes of resistant hypertension include the expansion of patients’ intravascular volume by either overconsumption of fluid or salt (sodium) retention due to chronic renal disease, or by the administration of sub-therapeutic doses of diuretics.
Finally, all patients with resistant hypertension must be assessed for causes of secondary hypertension like kidney-parenchymal disease, reno-vascular hypertension, sleep apnea syndrome or primary aldosteronism.
