Forms of congenital heart disease
All forms of congenital heart disease can be assigned to one of the following three major groups. Most common are congenital heart defects in the form of short-circuit connections with left-right shunt - especially in almost a third of cases of ventricular septal defect. Less common are congenital heart defects with right-left shunt. Below is an overview of forms of congenital heart disease. In brackets, the approximate frequency is given in% (according to "Competence Network Congenital Heart Defects").
Heart defect without shunt
- Pulmonary stenosis (7%): Constriction of the heart valve, which is connected between the right ventricle and the pulmonary artery. Depending on the degree of manifestation, the pulmonary stenosis leads to an increased load on the right ventricle, which must fight against an increased outlet resistance. The consequence of pulmonary stenosis can be heart muscle weakness of the right heart.
- Aortic stenosis (3-6%): Aortic stenosis is a narrowing of the heart valve that separates the left ventricle from the main artery. The aortic stenosis makes increased demands on the performance of the left heart muscle, which can be overtaxed in the long run.
- Aortic coarctation (aortic carotene, CoA, 5-8%): Severe constriction to constriction in the descending portion of the main artery. The aortic coarctation also predominantly burdens the left heart and leads to hypertension in the head and arms. Typically, the blood pressure measured on the legs is noticeably lower in the case of aortic coarctation than in the arms.
Heart defect with left-right shunt
In these heart defects oxygen-rich blood flows from the left into the right heart, ie from the body into the pulmonary circulation. The right heart is thereby increasingly burdened.
- Atrial septal defect (ASD, 7%): A hole in the septum of the heart that separates the two atria represents the atrial septal defect. Under normal circumstances, higher pressures prevail in the left heart than in the right, part of the bloodstream actually being should supply the organism, passed over the atrial septal defect back to the right heart. This portion of the bloodstream circulates in the wake again and again through the pulmonary circulation, without being available to the entire organism. In the long term, an atrial septal defect may result in congestion of the pulmonary circulation with pulmonary hypertension and heart muscle weakness of the right heart.
- Chamber Septum Defect (VSD, 31%): The ventricular septal defect is characterized by a hole in the cardiac septum between the right and left ventricles. As in the case of the atrial septal defect, in the case of a ventricular septal defect, a different proportion of the blood flow flows back into the right heart via the cardiac septum wall, whose muscular strength can not cope with the new pressure conditions. Chronic overworking usually results in myocardial insufficiency of the right ventricle from a ventricular septal defect.
- Endocardial cervical defects (atrioventricular septal defect, AVSD, 4.8%): Inadequate connection of the muscular and connective tissue structures at the transition between the atrial septum and the ventricular septum in varying degrees. In extreme cases, there is an open channel in an endocardial defect that extends from the atrial septum to the ventricular septum and causes a massive blood flow from left to right with stress on the right heart and pulmonary circulation.
- Persistent ductus arteriosus (PDA, 7%): The ductus arteriosus botalli is a short circuit connection between the pulmonary artery and the main artery, which has an important function for the unborn child in the womb, blood from the right heart past the non-functioning lung directly into the large circulation to guide (the oxygenation of the child's blood takes place in this phase namely over the lungs of the mother). If this short-circuit connection persists after birth, it favors the blood flow from the left to the right heart and thus leads to right-heart strain.
Heart defect with right-left shunt
In these heart defects, oxygen-poor blood flows from the right into the left heart. The left heart is thus increasingly burdened, the oxygen content in the blood of the large circulation decreases, which is noticeable as a blue coloration (cyanosis) of the lips and nails. These heart defects can be linked to complex vascular malformations, causing the bloodstream to be different than normal, which in turn can lead to increased rather than decreased pulmonary blood flow.
Right-left shunt with reduced pulmonary blood flow
- Fallot tetralogy (TOF; 5.5%): The combination of the following four (= tetra) malformations: pulmonary stenosis, defective main artery development, ventricular septal defect and increase in right ventricular muscle thickness. As pulmonary stenosis obstructs regular blood flow into the pulmonary circulation, some of the oxygen-depleted blood from the right heart alternatively flows to the left, thus lowering the oxygen content in the large circulation. Chronic oxygen deficiency of all organs is the result of a Fallot tetralogy.
- Pulmonary atresia or tricuspid atresia (1-3%): Incorrect formation of the pulmonary valve and / or tricuspid valve (flap between right atrium and right ventricle). A part of the oxygen-poor blood from the right heart must be passed in these anomalies either via an atrial septal defect or a ventricular septum defect in the left heart. In some cases, the pulmonary circulation is mainly from the main artery via a persistent ductus arteriosus into the pulmonary artery. In this heart defect must also be expected with severe impairment of circulation and oxygen deficiency of the organs.
Right-left shunt with increased pulmonary circulation
- Transposition of the Great Arteries (TGA, 4.5%): In this complex malformation, the main artery falsely originates from the right ventricle and the pulmonary artery from the left ventricle. Small and large circulation are therefore not connected in series but in parallel; the right heart supplies the large, the left the small circulation with blood. This heart defect can only be reconciled with life if additional short circuit connections on the atrial or chamber level ensure an exchange between both circuits. Since the right ventricle must apply the pressure of the large circulatory system, a rapid failure of the right heart is to be expected.
- Total pulmonary vein mesentery (TAPVC, <1%): The pulmonary veins open into the right atrium instead of into the left. The anomaly requires an additional short circuit connection between the right and left heart to allow the exchange between the small and large circulatory system and burdens both the pulmonary circulation and the right heart.
- Double outlet right ventricle (DORV, 1.2%): origin of both large arteries from the right ventricle): The left heart is involved in the bloodstream via a cardiac septal defect. Since the right heart has to supply both circuits at the same time, its congestion with right heart failure is inevitable.
- Double inlet left ventricle (DIVM 1.5%): In this anomaly, there is only one ventricle, rather than right and left ventricle, resulting in both blood oxygen saturation and blood circulation with heart failure.
- Hypoplastic left heart syndrome (HLHA, 3.8%): Inadequately developed left ventricle, which can not do its normal function. As a result, the circulation of the great circulatory system must be via the ductus arteriosus from the right heart. This very rare anomaly is incompatible with life under any circumstances.