What causes high blood pressure or hypertension

A normal or healthy blood pressure is not constant. The body regulates the blood pressure dynamically up and down to accomodate the needs of the body for the work load at the moment.

By hypertension the blood pressure is elevated. It may be elevated during heart contractions (elevated cystolic blood pressure), between the contractions (elevated diastolic blood pressure) or both. Usually also the dynamic regulating mechanism is injured, so that the blood pressure is not fitted to the work load at each moment.

There are many factors that can cause high blood pressure or a poor regulation of the blood pressure, and often these factors exist together.

- The smooth muscles of the blood vessel walls may contract exaggeratedly. This will decrease the volume of these walls and press the blood together, making the blood pressure higher. The decreased volume in the blood vessels will also force the heart to work harder to give the body enough blood throughput, and this will increase the blood pressure even more. Such an increased tension is often caused by a poor nerval regulation of the circulatory system.

- By hypertension there is often an increased blood volume and a general water retension in the body. This problem is often caused by elevated levels of salt and lipids in the blood, or by an imbalance between the minerals sodium and calium so that water is held back in the body.

- By hypertension there are also often hard, inelastic and narrow blood vessels caused by arteriosclerosis. Atherosclerosis is a aggregation of cholesterole, fat, calcium salts and cells in the blood vessel walls. This hinders the blood vessels to widen elastically by each heart contraction, and then the blood pressure is raised. The narrowing also forces the heart to work harder and also thereby cause the blood pressure to raise.

The primary causes behind these mechanisms are not fully understood, but these factors may contribute to causing hypertension:

- A high consume of salt, or sodium chloride. This is due to the high salt content of the averidge western diet. At the same time the body may lack potassium and other minerals.

- A high fat consume, and especially consume of saturated fat, chemically altered fat (trans fat) and omega 6 poly-unsaturated fat. This misconsume is due to a high intake of fat meat, fat diary products, snacks, cookies, margarine, soy oil and palm oil.

- Stress at work and in the daily life make the nervous system and hormonal system misregulate the circulatory system, and thus causing tension in the blood vessls and exaggerated heart work.

- Smoking gives the body a lot of toxic substances that hurt the tissues in the heart and blood vessels.

- Over-weight forces the heart to work harder, and causes atherosclerois that then increases blood pressure.

- Lack of exercise. Exercise stimulate the blood vessels to develop better capasity, and stimulate a better regulation of the circulatory system. It also helps prevent degeneration of the blood vessels by tissue damage and atherosclerosis.

- Kidney failure can cuse a bad electrolyte balance in the blood and body fluids, and thereby cause blood pressure.

What is angina pectoris

By angina pectoris the vessels supplying the heart itself with blood are too narrow. The narrowness will however vary from time to time because of vessel contraction or other factors.

Also physical strain sometimes demands a work load from the heart that demands a higher blood throughput than the narrow vessels are able to support. In these cases the heart will get an acute shortage of oxygen and nutrients. This wil give a sharp pain in the chest originating from the heart.


Symptoms of angina pectoris

Angina pectoris gives one or more of these symptoms:

- A crushing pain in the centre of the chest behind the breast bone, or at the left inside of the chest.

- An oppressive heavy and constricting feeling inside the chest.

-Pain that radiates from the centre of the chest to the arms

-There can also be pain in the jaw, throat, stomach or between the shoulder blades

The causes and mechanisms of angina pectoris

By angina pectoris, the blood vessels in the heart are permanently narrowed, often because of atheroslerotic thickening of the vessels. Artheroslerosis have a complex cause, but high blood colesterole contribute the the develpment of this condition.

By some situations, these vessels narrow even more, and the heart gets too litttle blood, for examples by psychological stress.

In other situations the blood becomes thicker and more hevily fluid than usual, and also now the heart gets too little blood, for example by extreme cold or after a heavy meal.

Platelets can also adhere to inside walls of the vessels and partially or entirely clog them, reducing the blood flow to the heart.

Other times physical exercise or heavy physical work load make the heart need more blood than usual, and the narrow vessels do not manage to conduct enough blood.

In these cases the heart gets too little oxygen and energy, and pain from the heart occur.


Medical treatment for angina pectoris

Acute angina pectoris is treated by medicines that make the muscles in the vessel walls relaxe and make the internal lumen graeter to let more blood flow through, for example tablets containing nitryglucerine.

Other types of nitrates than nitroglycerine which have a longer lasting effect are used for long term relaxation of the blood vessels and prevention of angina attacks.

Nitroglycerine mainly relaxes the veins that lead from the heart tissues. Thereby it makes it easier for used blood to leave the heart and for new blood to enter the heart. To some extend it also relaxes the arteries leading to the heart tissues. Thereby it ease the flow also in these vessels.

Beta blockers reduce the heart rate, the blood pressure and the oxygen need of the heart, and will therefore prevent angina attacks. Beta blocker block the effect of adrenaline ( epinephrine ) that increases the blood pressure.

Nicorandil, a potassium channel blocker also reduce the mucle tension in the vessel walls to let more blood pass.

Calcium-channel blockers also relaxe the coronary arteries to let more blood pass to the heart tissue.


Surgical techniques for angina pectoris

By very narrow vessels, surgery to delate or to exchange the narrowed vessels is sometimes performed.

The msot common surgical techique is dilation with a ballon. A thin catheter with a inflatable end is inserted into a blood vessel and pushed along until it reaches the right place at the heart. There the balloon is inflated, and the narrowed vessel is streched to a greater capacity. Sometimes a stent is also placed inside the vessel to hold it open. The techique is called PCI, PTCA, angioplasty, balloon dilation or balloon angioplasty.

By laser angioplasty a catheter that leads laser light is advanced to the narrowed place. The laser then burns away plaque that narrows the vessel.

By another techique, called atheractomy, a catheter with a rotating shaver is inserted to the blocked place. The placque that bloks the passage is then cut away.

These other techiques are also sometimes combined with a stent.

A more extensive surgery done in more serious cases is coronaryt bypass graft surgery. By this techique the chest is opened or surgical instruments are inserted through the chest wall. Then the blocked blood vessels are cut out and a new healthy vessel taken from elsewhere in the body is transplanted.

After having surgery done, it is necessary to change lifestyle so that the sites are not blocked once again.


Althernative treatment of angina pectoris

Natural supplememenst to help against angina have the aim of making the blood better fluid, to reduce the platelet adherence to the vessel walls, to relaxe the blood vessel walls, and to stimulate cleansing and repairing activities in the vessel wall tissue.