Almost every human being knows the tachycardia: one feels how the heart beats in one, it knocks and thumps and one can feel the pulse clearly down to the carotid artery. In stressful situations, with excitement, anticipation or heavy physical activity, rapid heartbeat is a normal reaction of the body and passes after a short time.
At rest, in an adult male, our heart pumps between 70 and 100 milliliters of blood per heartbeat into the systemic circulation (in women this amount is a little less). When the body is stressed, for example through exercise, there is a higher oxygen demand in the body and consequently a higher need for blood. Since the amount of blood pumped out of the heart per cycle can not be increased in large quantities, the body increases the rate at which it pumps blood into the circulation, the heartbeat.
Tachycardia in pregnancy can occur at any time and is frequently observed between the 28th and 32nd week of pregnancy. Especially during periods of rest, an increased palpitation of the heart occurs. Although the exact causes of occasional palpitations are not yet clear - one suspects a hormonal connection - this is in most cases not considered pathological.
If the tachycardia occurs very frequently and is accompanied by heart stumbling and irregularities, advice should be provided by a physician.
It may be due to a heart rhythm disorder. Tachycardia may also be associated with hyperthyroidism and then occur together with a so-called goiter on the neck. This is an abnormal enlargement of the thyroid tissue. If the tachycardia is accompanied by other symptoms, such as paleness, hair loss, muscle cramps, etc., it may be a lack of electrolytes.
A visit to a doctor is not absolutely necessary for uncomplicated heart racing. Even a drug therapy is not in question in these symptoms, best in this case, the body to give rest and time to get used to the new situation and adapt.
However, if the heart beats irregularly, "stumbles", or is a heart rhythm disorder known, it should be clarified by the doctor using an ECG.
Even if a thyroid disease is known, a heart rate should be clarified during pregnancy as a precaution by the doctor.
Tachycardia is also in need of clarification and treatment if, in addition to the heart rate, the blood pressure also greatly increases. In this case, a doctor should urgently be consulted and therapy should be started. Symptoms of high blood pressure include headache or a feeling of pressure in the head, blurred vision, dizziness and nausea. In some cases, increased urinary output (polyuria) may occur due to increased vascular pressure.
During pregnancy, the entire body is adapted to the needs of the growing child. It also means that the body forms more blood to ensure the care of the child. In some cases, this change is accompanied by the occurrence of palpitations. This is due to the fact that the heart has to transport nearly 50% more blood through the increased blood volume during pregnancy and accordingly increases its performance. The heart beats stronger and faster than before and this is what women perceive as unpleasant heart racing.
Severe stress can also trigger tachycardia or increase a mild heart rate. However, the heartbeat is almost always harmless and no cause for concern.
In most cases, the tachycardia resets after some time by itself, when the body has become accustomed to the new conditions of pregnancy.
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The need for magnesium increases during pregnancy, especially after the 22nd week of pregnancy. Magnesium is involved in many metabolic processes in the human body and is involved in the neural control of muscle activity.
The symptoms of a magnesium deficiency include tingling sensations of the hands and feet, increased nervousness and hypertension, and muscle spasms. Typically, calf cramps and tension in the back area occur.
Cardiac arrhythmias in the form of palpitations may also be an expression of magnesium deficiency.
The iron requirement is increased during pregnancy. If there is no compensation for the increased demand on the part of the diet and if the iron stores are exhausted, a deficiency arises.
A mild iron deficiency is noticeable with symptoms such as paleness, fatigue and concentration difficulties. A more advanced deficiency occurs with palpitations, shortness of breath and mood changes. Since iron is also a component of the red blood cells that transport the oxygen, the heart has to pump more in less oxygen transporters for an adequate supply of all organs.
Pregnant women belong to the risk group for iron deficiency and should therefore pay attention to an adequate intake.
The size of the thyroid gland increases slightly as a result of increased hormone requirements during pregnancy. However, if the increase in size exceeds a certain extent, it is called a goiter, which can occur in hyperthyroidism. Hyperthyroidism refers to overactivity of the thyroid and is a possible trigger of the heart. The autoimmune Graves disease causes hyperthyroidism and must be treated promptly. In addition, pregnancy-induced hyperthyroidism can be triggered by the hormone chorionic gonadotropin produced during this time. It is similar to the thyroid hormone TSH and stimulates the thyroid gland to increased activity. However, this form of hyperfunction is usually no longer found after the 20th week of pregnancy.
Hyperthyroidism is usually associated with a nonspecific symptoms of palpitations, sleep disorders, nervousness, sweating, hair loss and increased sensation of anxiety.
In hyperthyroidism there is an increased risk of so-called pre-eclampsia, a premature detachment of the placenta. The probability of premature and abortion as well as malformations increases.
Hyperthyroidism in pregnancy should therefore generally be treated with medication.
You might also be interested in this topic: Hyperthyroidism
If palpitations occur during pregnancy at night, this does not automatically have a pathological value.
During pregnancy, the expectant mother's heart is challenged to pump up to 40% more blood, not only through her own body, but also through that of her growing child.
In addition to the blood volume but also the altered pressure on organs and vessels as a result of pregnancy play a role. This is especially useful when lying down and leads, especially in more advanced weeks of pregnancy, to the forcing of the inferior vena cava, the so-called inferior vena cava. The large vessel carries the blood of the lower body back to the heart. If the resistance is increased in this way, the heart must pump more and increase its beat frequency. It is therefore a natural mechanism of the human body.
In supine position, the vessel is the most squeezed, so it is best to relax in a lateral position.
In the treatment of hypertension in pregnancy, the symptomatic treatment is the drug of choice, so bed rest, physical protection, as well as balanced nutrition.
For more complicated courses and persistent hypertension, drug therapy with alpha-methyldopa, beta-blockers or hydralazines may be considered.
Many more general information on this topic can be found at: Therapy of tachycardia
Another possible trigger for tachycardia in pregnancy is the so-called vena cava compression syndrome.
This is a pregnancy complication, which causes circulatory disorders of the mother by the pressure exerted by the child in the uterus on the inferior vena cava (inferior vena cava).
The syndrome occurs especially towards the end of the pregnancy, when the child has already reached a certain size and weight. This can happen when the mother is lying supine for a long time, pushing the uterus towards the vena cava, which carries blood from the lower extremity to the heart; thus the return flow of the blood to the heart is diminished. The heart registers that less blood arrives at it and tries to compensate for the reduced blood volume by measures such as an increased heart rate in order to continue to ensure a sufficient blood supply. However, the heart can not permanently compensate for this condition. If the compression of the vena cava by the uterus persists for a long time, it can lead to severe circulatory problems, such as low blood pressure and dizziness, to the point of shock and unconsciousness.
The vena cava compression syndrome and the associated syndromes can be resolved very quickly and easily by the pregnant woman in a lateral position. Preferably on the left side, as in this position, the vena cava is the most spared. The vena cava runs on the right side in front of the spine along the heart, accordingly it can still come in lateral position right to the compression of the vein. In left lateral position all symptoms and complaints should disappear within few minutes. Longer lying on the back should be avoided to prevent the syndrome.
In extreme cases, the Vena Cava Compression Syndrome can lead to life-threatening situations for both mother and child, triggering prematurity due to decreased blood supply to the child. Therefore, after a single onset of symptoms in the course of further pregnancy should be paid to the right reclining position, especially at night.
More information on this topic is available in the accompanying editorial: Vena Cava Compression Syndrome