Koch’s triangle is an intruiging area. On the atrial aspect, the triangular area itself is delineated by the tendon of Todaro, which inserts in the atrial aspect of the central fibrous body to mark the apex of Koch´s triangle. The ventricular border is formed by the septal leaflet of the tricuspid valve. The base of the triangle is marked by the inferior right atrium around the orifice of the coronary sinus (cavo-tricuspid isthmus), along with the musculature extending to the hinge of the septal leaflet of the tricuspid valve, i.e. septal isthmus. The anatomy and electrophysiological chararteristics of this region provide a substrate for different arrhythmias to develop. Chapter 1 is devoted to address to all these different aspects. In the first part an overview is given of the known embryology of the atrioventricular conduction axis and its direct environment, as well as the anatomy and electrophysiological characteristics of this region. Until now a lot of questions on its anatomy and physiology still exist, despite intensive research. As already mentioned, different arrhythmias can develop, which can be cured with transvenous radiofrequency (RF) catheter ablation, although some pitfalls still remain present.

Bard Benelux B.V., Cryocath Technologies Inc., ELA Medical Nederland B.V., Guidant Nederland B.V., Medtronic B.V., St. Jude Medical Nederland B.V., Vitatron
L.J.L.M. Jordaens (Luc)
Erasmus University Rotterdam
Erasmus MC: University Medical Center Rotterdam