Anterior view of the frontal section of the heart

Anterior internodal

Arch of aorta

Atrioventricular (AV) bundle (bundle of His)

Atrioventricular node

Bachman's bundle

Frontal plane through heart

Left atrium

Left ventricle

Middle internodal

Posterior internodal

Purkinje fibers

Right and left bundle branches

Right atrium

Right ventricle

Sinoatrial node