Unlike vascular rings, vascular loops do not completely surround the esophagus and trachea, but they can still compress them severely and cause symptoms. 

A typical example is the loop of the left pulmonary artery (LPA): The LPA first curves far to the right and then crosses between the esophagus and trachea to the left side. The abnormal path of the LPA between the esophagus and trachea causes constriction of the esophagus from the front and the trachea from the back. In addition, the LPA loop can occur in conjunction with a malformation of the trachea, in which the cartilage is formed as complete rings and may also be constricted.

Furthermore, the esophagus can be caused by a right subclavian artery (Arteria subclavia lusoria) that originates incorrectly from the descending aorta. In the area where the Arteria lusoria originates, the vessel can also be severely dilated (aneurysm), which can further exacerbate the symptoms. According to the first person to describe this condition, this enlargement or bulge is also known as Kommerell's diverticulum.

There is also the syndrome of compression of the brachiocephalic trunk, in which the trachea is constricted from the front by an artery (brachiocephalic trunk, which supplies blood to the right side of the head and neck and the right arm artery) due to a delayed departure of the trunk from the aortic arch.

A so-called loop of the aortic arch (circumflex aorta) is also very rare. In this case, there is a left aortic arch, but the descending aorta does not descend to the left, but crosses directly back to the right, which can lead to constriction of the windpipe or esophagus.

Normally, the trachea is held open in the front by cartilaginous rings. In the back, it is closed by a layer of muscle. 

Due to the pressure of the vascular loop (typical in LPA sling and compression syndrome of the brachiocephalic trunk and in circumflex aorta) can cause narrowing and softening of the cartilage rings (tracheomalacia), which can lead to a typically exacerbated breathing sound (stridor) during inhalation and exhalation. Another reason for this breathing sound can also be a congenital narrowing of the windpipe (tracheal stenosis). In this case, the windpipe is often made up of complete cartilage rings instead of cartilage slats. Sometimes breathing difficulties are not recognized early on or are misinterpreted as asthma. In most cases of these vascular malformations, the body and lung blood flows do not mix, and therefore patients do not show signs of cyanosis or symptoms of heart failure such as sweating or poor growth. 

The arteria subclavia lusoria causes difficulty swallowing because the artery (and possibly also the Kommerell diverticulum) crosses behind the esophagus, constricting it from behind.

At the DHZC, we offer patients various diagnostic procedures. The diagnosis is often made during pregnancy using high-resolution ultrasound. After birth, the most important examination methods are: echocardiography, magnetic resonance imaging  (MRI), computed tomography (CT) and bronchoscopy. This involves inserting a probe into the trachea to examine the narrowing and, if necessary, the entire cartilage rings. If the course of the vessels is unclear, angiography may also be necessary for clarification.

At the German Heart Center at Charité, we perform these very rare procedures on a routine basis. Even after corrective surgery, infants often require special intensive care follow-up, sometimes even a temporary tracheotomy. Our intensive care unit is staffed by pediatricians, pediatric intensive care physicians, and pediatric intensive care nurses with years of experience. They are familiar with these respiratory problems and can identify issues early on and treat them promptly. 

Our extensive experience with such a rare and complex heart defect is reflected in the excellent postoperative progress of our patients. Further information can be found in our externally validated quality assurance standards and annual quality reports.

To the pediatric heart surgery quality report

The prognosis after correction of the vascular loop is generally good, and the symptoms are largely resolved. However, after the vascular loop has been severed, the reimplanted vessels may become narrowed again over time.

Therefore, in the weeks, months, and even years following the operation, regular check-ups with a pediatric cardiologist must be carried out in order to closely monitor further development and detect any narrowing.

When the sternum is cut lengthwise, it usually takes about four to six weeks to heal completely and become stable. After that, there is nothing to prevent normal physical activity.