Diastole Too Low - Is It Dangerous?
The heart action is divided into two sections: the expulsion phase in technical terms called systole and the filling phase, also known as diastole. The causes of low diastole are diverse, although there are harmless reasons, but there are also many that require treatment, which should be clarified with a doctor. Very often, however, a low diastolic value is related to a generally low blood pressure and does not represent a danger. By definition, a diastolic blood pressure is too low if the value is below 60 mmHg.
Causes of Low Diastole
The most common causes of decreased diastole are listed below. You will then find a more detailed explanation of the clinical pictures.
- Varicose veins
- Heart failure
- Valvular heart disease
- Orthostatic neuropathies
- low blood pressure during pregnancy
Hypotension as a possible cause
There are many causes of hypotension, the most common being idiopathic. This means that no cause can be determined. It mainly affects younger women with a slim, petite build and is affected by infections and lack of exercise, e.g. can benefit immediately after an operation.
If there is no idiopathic cause, it is called secondary hypotension. Again, it can have various causes. One of them is too little blood volume for the vessel size. This can be an absolute lack of fluids, e.g. after severe blood loss or a relative deficiency. This means that there is enough fluid in the body, but it is distributed to the detriment of the organ systems. This is the case, for example, in allergic shock, in which the blood migrates to the periphery (skin) and there is too little blood for the central organs to maintain normal blood pressure.
The thyroid as a possible cause
The thyroid intervenes in blood pressure regulation. The thyroid produces the hormones T3 (Triiodothyroxine) and T4 (Thyroxine). These two hormones have a very diverse function in the body and act on many organs.
In general, they stimulate the metabolism and thereby increase energy and oxygen consumption. The thyroid hormones also have an effect on the heart. There are so-called beta receptors, which are increasingly built into the surface of the heart muscle cells under the influence of T3 and T4. When activated, these beta receptors increase the contraction force of the heart, which, among other things, is of decisive importance for increasing blood pressure.
Another point of attack of the thyroid hormones are the walls of the blood vessels, which expand under their influence (so-called. Vasodilation) and thus lower blood pressure.
An excess of hormones is produced in people with an overactive thyroid. As a result, beta receptors are increasingly presented on the surface of the heart cells and the systolic value rises in those affected. Due to the increased hormone level, the blood vessels expand and the diastolic value is reduced. As a result, people with hyperthyroidism often have a larger range between systolic and diastolic blood pressure.
An underactive thyroid (Hypothyroidism) is usually shown by reverse changes, namely a decrease in the systolic and an increase in the diastolic value.
Find out all about the topic here: Overactive and underactive thyroid glands.
Heart failure as a possible cause
Cardiovascular disease can also be the cause of hypotension. On the one hand, it can be a case of heart failure, which means that the heart as a “pump” is broken and therefore ineffective. Less and less blood is ejected and consequently the blood pressure also drops over time, if it can no longer be compensated by other mechanisms.
The heart valve defect as a possible cause
However, heart valve defects can also be responsible for arterial hypotension. Diastolic hypotension is particularly typical of aortic valve insufficiency. The valve separates the left ventricle from the main artery (aorta) and ensures that no blood flows back from the aorta into the heart during diastole (filling phase). If the valve becomes permeable (insufficient), blood flows back into the heart with the result that the diastolic blood pressure drops.
The varicose veins as a possible cause
Furthermore, low blood pressure can be caused by insufficient venous blood flow back to the heart. This is e.g. the case with varicose veins. The blood can no longer flow out properly and builds up in the legs, with the result that this volume is lacking in the other vessels or the heart in order to keep the blood pressure at a normal level.
Orthostatic neuropathy as a possible cause
Autonomous neuropathies (diseases of the peripheral nervous system) mainly cause orthostatic dysregulations. Especially in the asympathetic form, the diastolic blood pressure and occasionally the heart rate are lowered.
Medicines as a possible cause
In addition, low diastolic blood pressure can also be induced by taking medication, e.g. in the treatment of isolated systolic hypertension. This is a form of high blood pressure for which the systolic value alone is too high.
If systole is high and diastole is low, what can be the cause?
Usually both the systolic and diastolic values are increased or decreased together. However, if the systole is increased and the diastole decreased, one speaks of an isolated systolic hypertension. Values are for example 150 / 50mmHg and are characterized by a large difference between the two values. There are usually two possible mechanisms behind this manifestation.
One reason for the isolated increase in systole can be severe calcification of the blood vessels. As a result, these lose their elasticity and cannot adequately buffer the rapid rise in blood pressure in the ejection phase of the heart because they can no longer expand sufficiently.
Another cause can be a malfunction of the aortic valve, which is located between the left ventricle and the main artery (aorta) is located. This means that on the one hand the heart has to fight this resistance with increased strength and thus an increased systolic value. On the other hand, if the valve is inadequate, blood can flow back into the heart during the relaxation phase and thus lower the diastolic blood pressure in the vessels.
The above-described hyperthyroidism, which dilates the vessels and at the same time increases the contraction of the heart, can exacerbate the large amplitude between systole and diastole.
More information on the topic Aortic regurgitation you'll find here.
Low diastole but high pulse?
In people with low blood pressure, the pulse often rises to compensate for it. Due to the low diastole, the blood is not sufficiently conveyed to the organs and peripheral extremities. There is a lack of oxygen, which is then compensated for by an increased heart rate.
Resting pulses above 100 beats per minute are considered too high and require clarification. However, a high pulse does not always imply a pathology, because the heart rate is influenced by many other factors such as stress, time of day, hormones and stimulants such as alcohol or drugs.
Low diastole in pregnancy
During pregnancy, especially in the last third, many women suffer from low blood pressure. This is preferably the case when lying on your back and when sleeping.
This is due to the fact that the embryo, which is becoming larger and, above all, heavier, squeezes the central blood vessels aorta and the inferior vena cava.
Since these vessels run directly in front of the spine, the vessels constrict, especially in the supine position, as the embryo follows gravity and presses on the mother's back. The constriction of the vena cava means that less blood comes back to the heart and the heart can no longer fill up sufficiently. As a result, it pumps less blood into the circulation and the pressure drops. There is really nothing you can do about it other than avoid lying on your back.
Read more about this under: Low blood pressure during pregnancy
Which diastolic value is considered dangerous?
The diastolic blood pressure value indicates the pressure in the blood vessels during the relaxation and filling phase of the heart. This diastolic value should ideally be less than 80mmHg and not fall below 60mmHg. These values are referred to as hypotension, or blood pressure that is too low
Compared to high blood pressure, however, it is less dangerous and has no long-term consequences. It only becomes dangerous for the body if the diastolic value drops very quickly or remains much too low for a very long time.
If the pressure in the vessels drops, not enough blood is transported and accordingly too little oxygen reaches the organs and the body periphery. A lack of oxygen in the brain manifests itself symptomatically as dizziness and fatigue. An oxygen deficit in the extremities is indicated by cold hands and feet.
Symptoms of low diastole
Symptoms of low blood pressure include poor performance, difficulty concentrating, tiredness, dizziness, ringing in the ears, shivering, cold hands and feet, turning black when standing up to fainting (circulatory collapse). This amount of symptoms can or does not appear.
Many people have hypotension (low blood pressure) and are unaware of it. The big difference to high blood pressure is the motto: Treatment is only given if the person suffers from it. Because contrary to hypertension, no permanent damage from an existing low blood pressure is known. The indicated symptoms can occur, which can be stressful for each individual, but structural changes or damage to the blood vessels are only associated with the existence of high blood pressure.
As a result, the symptoms are harmless.
Read more on this topic at: Symptoms of low blood pressure
The simplest and safest means of diagnosis is to measure blood pressure. To check whether the blood pressure is permanently low, a 24-hour blood pressure measurement is often carried out.
The normal value for diastolic blood pressure is between 60 and 90 mmHg. A distinction must be made here between hypotension and orthostatic dysregulation. Long-term diastolic blood pressure values below 60 mmHg are referred to as arterial hypotension, whereas orthostatic dysregulation is characterized by a brief drop in blood pressure when standing up or standing up. This is because quite a bit of blood sinks into your legs when you get up. The heart does not have enough blood to fill completely and this leads to a drop in blood pressure. The sudden loss of pressure can lead to brief loss of consciousness, which is colloquially known as circulatory collapse.
The basic therapy consists of drinking enough water to prevent a lack of fluids. The consumption of table salt can be increased as a support and sporting activity can also be used for cardiovascular training.
In addition, hypotension can also be treated with medication, but this is only done if the patient complains of symptoms. Then mineral corticoids, sympathomimetics or dihydroergotamine are available. If this option is an option for you, the best thing to do is to see a doctor and seek advice.
Medicines as a therapy option
There are several different groups of drugs that can increase diastolic or total blood pressure. However, these are usually also associated with possible side effects, so that non-drug options, such as the home remedies listed below, should be tested first. In general, it should first be clarified what cause the low blood pressure is based. These diseases should first be treated.
Drugs to increase blood pressure can be divided into four classes:
The first group are the so-called sympathomimetics. These work in a similar way to the body's own hormones adrenaline and noradrenaline and increase the contraction force of the heart and the return of blood to the heart.
The second possibility are vasoconstrictors, which mainly constrict the venous vessels and thus the blood is more available in the arterial circulation. A well-known drug in this class is dihydroergotamine.
Furthermore, the supply of mineral corticoids can be useful. These are normally produced in the adrenal cortex and prevent salt and water from being excreted in the kidney, which keeps blood volume up and thus increases blood pressure.
The fourth option is the administration of erythropoietin, which stimulates the maturation of red blood cells (med. Erythrocytes) promotes in the bone marrow and thus more oxygen can be bound and made available to the organs.
In emergency situations such as shock, infusion solutions with electrolytes increase the blood volume and raise blood pressure values that have fallen sharply.
Find out all about the topic here: Medicines for low blood pressure.
Home remedies as a therapy option
There are numerous home remedies and ways to increase blood pressure, which should be tried out before taking any medication and thus spared drug therapy.
One cause of low blood pressure is a lack of blood volume. This can be increased by a balanced and salty diet. An increased salt content in the blood leads to water. In general, it is advisable to drink two to three liters of fluids daily. Sodium-rich mineral water, tea, or fruit juices are best.
Another way of counteracting low blood pressure is to take measures to get the circulation going. This includes sports of all kinds (for example swimming, jogging, cycling, hiking and much more) but also activities such as walking, gymnastics, yoga or dancing. In addition, alternating showers with cold and warm water can be very helpful. So that the blood does not sink too much in the legs, especially when getting up quickly or standing on one spot for a long time, support and compression stockings are recommended, which facilitate the return flow to the heart.
In addition, those affected should avoid getting up too quickly, as in the worst case scenario, dizziness or fainting can occur.
Homeopathy as a therapy option
Many natural and homeopathic substances are said to have a blood pressure-increasing and circulatory stabilizing effect.
A helpful substance is hawthorn, which increases the heart's pumping power and at the same time improves the oxygen supply to the heart by widening the coronary vessels. In addition, it has a lowering effect on high blood pressure and is therefore ideal for a good blood pressure setting without outliers up and down.
A second effective homeopathic remedy is Haplopappus, which is obtained from Baylahu herb and also directly increases blood pressure.
You can find more information on this topic here: Homeopathy for low blood pressure.
Significance of blood pressure for diastole
What do the phases of the heart's action have to do with blood pressure?
There is a certain pressure in the vessels, the diastolic blood pressure, which is caused by the blood in the vessels when the heart is in its "resting phase", i.e. when it is being filled. This depends on the amount of time the heart pumps and the size of the vessel diameter. The diastolic blood pressure should be around 80mmHg (read: millimeters of mercury).
In the expulsion phase, however, the heart has to generate a higher pressure than the diastolic pressure so that the blood can be pumped into the vessels. Because the blood always flows from higher to lower pressure. During systole, the heart generates a pressure of approx. 120 mmHg, which is pumped into the vessels and from there passed through the body's circulation. During the filling phase of the heart, the blood pressure drops back to the diastolic "low point". The blood pressure is thus made up of two values, a systolic and a diastolic: 120/80 mmHg (normal value).
These two values can be abnormally increased or decreased. One speaks of low diastolic blood pressure when it is below 60 mmHg.