Congenital heart defects

Diagnosis and therapy

Congenital heart defects range from simple problems with very little effect on cardiovascular functions to far more serious cases in which the defect can lead to premature death if left untreated. Patients with moderate-to-severe heart defects who do not receive surgical or interventional therapy can expect to have a significantly reduced life expectancy. Thanks to modern diagnostic techniques, most heart defects today are detected before a child’s first birthday.

Severe heart defects restricting the supply of oxygen often impose such a strain on a newborn infant that they require extremely rapid treatment.

The prenatal diagnosis of congenital cardiovascular malformations has improved in leaps and bounds over the past few years. Many severe heart defects can now be diagnosed before the child is born. This makes it possible either to plan an interruption of pregnancy if necessary in cases of severe malformation, or to ensure that the newborn child receives the best possible treatment after birth.

Certain types of heart defect are accompanied by audible heart murmurs caused by vascular or valvular stenosis or a shunt. These murmurs can be detected by means of a simple stethoscope examination. On the basis of their noise patterns, it is possible to draw conclusions as to the origin of the sound and thus also the location of a given valvular deformation or the location of shunts.

Another method used to detect congenital heart defects is the electrocardiogram (ECG). By recording the heart’s electrical activity, it is possible to establish its size and position, and to detect any cardiac arrhythmias.

However, the most important diagnostic examination method at present is echocardiography. This ultrasonic analysis enables all the structures of the heart to be presented accurately, and nearly all defects to be displayed. In addition, it can be used to assess the function of the heart and its individual components. This examination method is generally employed at the slightest suspicion of a congenital heart defect. It is pain-free and poses no risk to the patient.

Other, more specialised, examination methods used according to the type of suspected congenital heart defect include cardiac catheterisation (CC), during which an interventional operation can be carried out at the same time, magnetic resonance tomography/imaging (MRT/MRI) and computerised tomography (CT).

All therapeutic heart operations, both surgical and interventional (with a catheter), have the objective of closing defects such as holes and connections, eliminating stenoses (constrictions) or repairing valves so that they no longer leak.

Some congenital heart defects, such as holes in the ventricular septum (VSD) or the atrial septum (ASD), can be closed completely by catheter intervention or surgical operation. Patients with these kinds of heart defect are subsequently cured, and have a normally functioning heart after the operation. However, this only applies to a very small number of congenital heart defects. In most cases, patients suffer from moderately severe heart defects which, though they can be corrected by means of a surgical operation, will always remain a ‘repaired’ heart.

In cases of severe heart defects, or children in poor physical condition, it is sometimes necessary to carry out a palliative operation before corrective surgery. This is done, for example, by inserting a shunt (connecting tube) between the aorta and the pulmonary artery in order to improve oxygen saturation for a certain period of time so that the child can develop more strongly. Only then is the corrective operation performed. Some palliative operations are definitive. They are primarily employed in cases of very severe congenital heart defects involving altogether missing valves or parts of the heart chamber, for example single-ventricle tricuspid valve atresia. During these operations the heart is corrected in such a way that it can supply two separate bloodstreams so that there is no, or at least less, mixing of oxygen-rich and oxygen-poor blood. This helps to eliminate or reduce cyanosis (blue disease).

There are specific types of surgical and interventional operations for each kind of heart defect. We will not attempt to list all the different methods here, but suggest you read the publications of the relevant self-help groups such as IDHK or Herzkind e. V.

Author: Dr. med. Ulrike Bauer
Last update: December 01, 2011