Fetal arrhythmia (FA) is one of the more common cases of pregnancy abnormalities, with rates ranging from 1 to 2 per cent of the total number of pregnancies, mostly in the middle and late stages of pregnancy. The majority of foetal heart disorders are transient and are a benign process in the development of the foetus ‘ s heart and do not require urgent treatment. However, about 10 per cent of rapid or slow foetal cardiac disorders persist or progress, leading to major organ regenerative damage and foetal heart failure, and even to premature birth and death. Accurate prenatal diagnosis and timely and appropriate intervention are therefore important for improving the prognosis of the foetus and pregnant women.
I. EMERGENCY MECHANISMS:
(1) The maternal factor: the addiction of pregnant women to tobacco and alcohol during pregnancy, the consumption of foods of stimulants such as caffeine, etc. increases the incidence of constrictive heart disorders, or the combination of mother ‘ s illness, etc.
(2) Feetal factor: The physiological factor is related to the incomplete development of the foetus and the prognosis is good. Reasonable pathological factors such as severe foetal oxygen deficiency, persistent heart disorder due to viral infections or congenital cardiac abnormalities, etc.
Classification:
Fetal cardiac disorders can be broadly divided into three categories according to the frequency and rhythm of the fetus heart rate: rapid heart disease, slow heart disease and heart disorder.
Diagnosis criteria: (1) Fetal heart rate continues to exceed > 180 times/min, the most common of which is a rapid cardiac disorder; (2) Fetal heart rate continues to be 25 to 30 times/min is that the heart of the foetus is not in line.
Diagnosis:
The usual diagnostic methods used for foetal heart disorders include prenatal consultations, continuous foetal care, electrostatics of the foetus and ultrasound cardiac maps of the foetus. Acoustic and continuous foetal care does not allow for the classification of foetal cardiac disorders, which, like the foetal electrocardiogram, does not reflect the structure of the foetal cardiovascular morphology and blood flow mechanics. These advantages are combined with the fetus ultrasound, which is the main means of prenatal diagnosis of foetal heart disorders. In recent years, the foetal cardiomagnetic map has been gradually applied to the diagnosis of foetal heart disorders.
IV. Diagnostic criteria:
The complete diagnosis of foetal cardiac disorders includes the fetus cardiac rhythm, cardiovascular structure and heart function assessment.
Fetal cardiac disorders mean that in the absence of hysteria, the rhythm of the fetus is irregular or the heart rate is outside the normal range (120-160/min).
(a) The heart rate of the foetus is diagnosed as excessive if it is below the lower limit of 20 per cent > 10s;
(a) Cardiac hypervelocity if the upper limit of 20% of the normal heart rate is sustained >10s;
The abnormal heart rate of the fetus means that the heart rate of the foetus is in the normal range, but the difference between the fastest and slowest heart rate is 25-30 times/min, including, inter alia, the early heart rate of the foetus, the second degree AVB and the long QT syndrome.
All types of foetal cardiac disorders, if lasting < 10 min, are transsexual foetal cardiac disorders, often repeated, disappearing and sometimes even changes of the FA type.
The earliest diagnosis of foetal heart disorders was about 16 weeks old, whereas the best diagnosis was 18-22 weeks. As a result, the examination of the heart of a child during the middle pregnancy, especially when it is 16-20 weeks old, is conducive to early detection of rational foetal disorders and avoid delays in diagnosis and missing the best time for treatment.
V. Indicators and principles of prenatal intervention:
The general principles of prenatal care for foetal heart disorders are: effective control of the FA, in the context of ensuring the safety of pregnant women, to minimize the negative effects of the fetus-morbidity, to restore, to the extent possible, the intrauterine environment, to reduce secondary damage to vital organs of the foetus, to provide a comprehensive assessment of the timely delivery of the foetus after its growth and development, and to promote the possibility of continued post-partum treatment.
VI. Intervention strategies:
Antenatal treatment for foetal heart disorders includes: 1 drug treatment via placenta transfer; 2 drug treatment through umbilical inoculation; 3 drug treatment through abdominal cavity; 4 treatment through amniotic cavity; and 5 intravivietal injection. (b) Injection within the foetal muscle, which can lead to neural damage to the foetal sepsis or to skin fractures and other injection injuries, as well as to different levels of foetal trauma from the abdominal cavity, amniotic cavity, etc. As a result, the treatment of drug trans-shipment through placenta is limited in clinical applications because of its intrusive nature and is still preferred by FA treatment, which is considered only at a very low rate of serious fH transfer.
VII. Prognosis:
About 90 per cent of foetal cardiac disorders are short-lived, isolated, pre-temporal contractions, more than disappearing late in pregnancy or after delivery, and are good. Combining foetal cardiac abnormalities, CAVB, FH, ambulatory fibrosis, expansive myocardiosis and are risk factors for slow prognosis of FA.
An unborn or newborn child affected by an abnormal rate or rhythm in the foetal womb
