Treatment of Fallot's tetralogy abroad
Fallot’s tetralogy or cyanotic congenital heart disease has severe hemodynamic disorders. It consists of four anatomical components:
- 1 - Displacement of the aorta into the right ventricle by more than 50%
- 2 - Stenosis (constriction) of the pulmonary artery
- 3 - Defect of the interventricular septum
- 4 - Hypertrophy (thickening of the wall) of the right ventricle
Causes of Fallot’s tetralogy
Fallot’s tetralogy cause underlies in the abnormal cardiogenesis (maldevelopment of the heart) during the 2nd to 8th week of prenatal development.
Problem can arise due to the genetic mutations or environmental factors like:
- Viral infections (measles, rubella)
- Medicines administration
- Drug addiction or impact of the industrial poisons
Fallot’s tetralogy is peculiar for certain chromosomal syndromes: Patau, Down, Edwards. Disease is often associated with other heart defects.
Symptoms of Fallot’s tetralogy
There are three syndromes playing a key role in the Fallot’s tetralogy clinical course:
Hypoxic crises arise as a result of the increased blood flow through the defect of the interventricular septum into the aorta. A patient develops suffocation attacks accompanied by cyanosis (blue shade) of the skin. There is a paroxysmal increase in dyspnea. Cramps or loss of consciousness are possible.
Trigger factors of hypoxic crisis are:
- Increased physical exercis
- Nervous excitement
Pathological vicious circle occurs. On one hand, oxygen reduction in the blood causes a rapid increase in respiration frequency. However, increased respiration leads to an increase in venous return to the heart, which only strengthens dyspnoea.
Polycythemia (erythrocythemia) is an increased formation of erythrocytes in the bone marrow (red blood cells transporting oxygen) arising due to the low oxygen level in the blood. New cells, though, have an inferior cell membrane, which prevents them from fully fulfilling the gas transport function.
Secondary immunodeficiency develops due to a deficiency of oxygen in the blood manifested by bacterial complications.
Other sympotoms of Fallot’s tetralogy are:
- Lag in physical development
- Resting dyspnea
- Cyanosis (blue shade) of the skin
- Thickening offingers distal phalanges in older children
When listening to the heart with a phonendoscope, the doctor determines a number of auscultative symptoms of Fallot’s tetralogy.
Diagnostics of Fallot’s tetralogy
ECG and echocardiogram are in the basis of the diagnostics. Electrocardiography and physical examination of a child helps only to suspect a diagnosis.
It is established after echocardiography (ultrasound of the heart) when the doctor sees:
- Aortic expansion and its displacement to the right
- The location of the aorta above the high defect of the interventricular septum
- Narrowing of the pulmonary arteries
- Thickening of the wall of the right ventricle and widening of its cavity
- Underdevelopment of pulmonary arteries and their branches
Treatment of Fallot’s tetralogy abroad
Drug therapy is only prescribed to support patient’s life and block attacks of hypoxia. Main treatment technique is surgery, which is a radical intervention performed at the age of 6 months to 3 years. Until the moment of surgery, it is possible to do palliative treatments aimed at the patient’s life maintenance, but they don’t compensate the defect completely.
Fallot’s tetralogy with accompanying pulmonary valve agenesis, radical treatment is required in the early age, normally from 3 to 6 months old or even earlier. This is necessary to prevent the compression of the tracheobronchial tree and to ensure the normal development of the respiratory tract.
Surgery before 3 months old is indicated if:
- There is a dependence on intravenous administration of prostaglandins during pulmonary atresia
- There is a progressive cyanosis within a few weeks after birth
- Oxygen saturation of blood is less than 80%
- There are hypoxic crises
A surgeon closes the defect of the interventricular septum and eliminates the stenosis of the pulmonary artery.
A patient must do regular check-ups every 6 to 12 months after the surgery and recovery.
The risk of bacterial endocarditis remains high. Prophylaxis of this disease is necessary life-long, according to the indications. The essence of prophylaxis is the prescription of antibiotics for any invasive manipulation, including dental.
Prognosis for Fallot’s tetralogy
Life prognosis is unfavorable for a patient suffering from Fallot’s tetralogy if the pathology is not treated. Lethal outcome will occur with the next hypoxic crisis due to oxygen starvation of the brain.Bacterial infections progressing because of the secondary immunodeficiency are the less common reason of death.
If no surgical treatment provided, there is following data:
- 35% of patients die within first year of life
- 50% of patients don’t survive to 3 years
- Median patients’ life length is 12 years
- Only 5% of patients are able to survive till the age of 40
Life prognosis after the surgery is favorable. Intraoperative and early post-operative mortality in top German hospitals doesn’t go over 4%. Meanwhile, these numbers can reach 8-10% in certain still developing countries.
Many patients may develop failure of the pulmonary artery valve after the surgery. This condition needs to be treated surgically with the help of an artificial valve placementduring the surgery.