Brief History
This procedure, a form of atrial switch, was developed and first performed by Senning in 1957 as a treatment for d-TGA (Technical aspects
With the Senning surgical repair, a baffle – or conduit - is created within the atria that reroutes the deoxygenated blood coming from the inferior and superior venae cavae to the mitral valve and therefore to the pulmonary circulation In the Footsteps of Senning: Lessons Learned From Atrial Repair of Transposition of the Great Arteries. Review Dodge-Khatami A, Kadner, A , Berger F, et al.Ann Thorac Surg 2005;79:1433-1444 This is accomplished by creating a systemic venous conduit that channels deoxygenated blood from the superior and inferior vena cava towards the mitral valve. After this complex plastic reconstruction using flaps from the right atrial tissue and the interatrial septum and lets the oxygenated pulmonary venous blood flow to the tricuspid valve and from there to the systemic circulation. The anatomic left ventricle continues to pump into the pulmonary circulation and the anatomic right ventricle will work as the systemic pump, in other words the ventriculo-arterial mismatch is left unrepaired. In the Senning's operation, atrial tissue is used to create the baffle. No prosthetic material is introduced. A complex work of incising and refolding of the native atrial tissue - which is so technically complex that has been referred to as "origami", is necessary to build the venous baffle. Indeed, the Senning technique was difficult to reproduce and was not widely embraced. In 1963, Mustard described an alternative technique, theAlternative surgical techniques
Currently, the arterial switch or Jatene procedure is the preferred surgical corrective method. In this technique, the great arteries are excised and reimplanted to the corresponding ventricles. The Brazilian surgeon Jatene performed the first procedure in 1975. The coronary arteries are also explanted from the anatomical aorta, which lies on the venous side and reattached to the systemic great vessel. Indeed, the initial difficulties that prevented an earlier adoption of this approach were mostly the inability to transfer the coronary arteries, besides problems with early forms of cardiopulmonary bypass that made cardiac surgery in early infancy less safe than in the present timesIn-hospital mortality
The acute mortality associated with the Senning procedure is reported to be around 5-10%. Patient selection and complexity of the congenital malformation are determinants of mortality risk.Late sequelae of the Senning procedure
Patients who have undergone such surgical correction of the congenital transposition are exposed to long term risks of cardiovascular events. In particular sinus node dysfunction, atrial arrhythmias, ventricular arrhythmias including sudden cardiac arrhythmic death, heart failure due to anatomically right ventricular failure or venous obstruction at the level of the baffle or caval anatomy have been described. The high chance of developing arrhythmias results in up to 25% of patients who have undergone a Senning or Mustard procedure having a pacemaker by adulthood. Long-term studies have disclosed that although from the functional capacity (NYHA Class) standpoint the Senning and the Mustard operation are similar, there is a higher risk of sinus node disease and arrhythmias with the latter. Overall, in most studies the survival is good into the second decade post procedure. 78% of patients were alive after 16 years in a large follow up study from the Netherlands. Before the utilization of surgical repair, Kirklin reports that the mortality associated with unrepaired TGA was 55%, 85%, and 90% mortality rates at 1 month, 6 months, and 1 year, respectively. This numbers correspond to all types of TGA. A major factor affecting long term morbidity and mortality is the coexistence of aCurrent use of the Senning procedure
Over the last 5 decades, the Senning procedure and its modifications have had variable degrees of popularity but are still of interest, also because hundreds of patients survive with such correction. Still in 2011, some patients diagnosed with d-TGA are not candidates for an arterial switch, particularly because of late diagnosis, coexistent VSD with associated pulmonary hypertension, inadequate left ventricular function or complex coronary abnormalities. Moreover, the Senning procedure is used as part of the double switch surgical correction of l-TGA ( Senning-Rastelli procedure).References
{{Reflist Cardiac surgery