The "single ventricle" does not describe a specific heart defect. Rather, it summarises various heart defects in which there is only one functional ventricle. The term univentricular heart is also used more frequently.
It is assumed that one mechanism why a ventricle lags behind in development is that not enough blood is supplied to this ventricle before birth and it therefore lags behind in development. Examples of such malformations are
- Tricuspid valve atresia
- Mitral valve atresia
- Double inlet left ventricle (DILV)
- Imbalanced atrioventricular septal defect
- Double outlet right ventricle (DORV)
If the AV valves between the atria and ventricles are completely closed (tricuspid atresia, mitral atresia), the corresponding half of the heart cannot develop and the outlet from these small chambers is also underdeveloped. These clinical pictures are then called Hhypoplastic right heart and hypoplastic left heart.
In a single ventricle, however, additional malformations such as transposition of the large arteries, aortic isthmus stenosis and underdevelopment of the aorta and pulmonary artery are possible. The single ventricle is therefore a complex heart defect.
What are the effects of single ventricle?
Corrective surgery is not possible for these complex heart defects. The aim of treatment is to gradually separate the systemic and pulmonary circulation (palliative surgery). Depending on which chamber and which artery is affected by the underdevelopment, the lungs may receive too much or too little blood. The necessary operations also depend on this.
Symptoms
What all patients have in common is cyanosis, although this can vary in severity. The demands on the only available ventricle to maintain the circulatory situation are enormous and so there are signs of heart failure with increased sweating, poor drinking behaviour, strained breathing and limited resilience.
How is the single ventricle treated?
Due to the many different types of single ventricle, surgical treatment varies greatly. The various procedures are listed here as an overview and explained in more detail in the Surgery section of this website.
Aortopulmonary shunt
Central shunt, modified Blalock Taussig shunt
Pulmonary artery banding
Central PA banding, bilateral PA banding, Blalock-Hanlon operation
Norwood-type surgery
Damus-Kaye-Stensel operation, Norwood operation, Sano operation, hybrid procedure (Comprehensive stage II)
Glenn operation
Bidirectional Glenn anastomosis, Hemifontan operation
Fontan-type surgery
Total cavopulmonary anastomosis (TCPC): Extracardiac tunnel, intracardiac tunnel, intra-extracardiac tunnel