Dimensions of the triangle of Koch in humans

Abstract

The atrioventricular (AV) node is situated in the lower atrial septum at the apex of a triangle described by Koch. 1 The sides of Koch's triangle are formed by the tendon of Todaro and the tricuspid annulus. The base is marked by the coronary sinus orifice (Figure 1). At the apex of the triangle the AV node penetrates the central fibrous body to become the His bundle. Increasing interest is now focused on this region because several techniques have been developed for the cure of supraventricular arrhythmias arising near the AV node. 2–4 Both surgical and catheter ablation techniques make use of the anatomic landmarks of Koch's triangle. 2–4 The aim of the current study was to define the size and variability of Koch's triangle in the human.