[Anatomy of the atria for rhythmologists].
The anatomy of the atria is always in the mind of interventional rhythmologists. There is a mental superposition of the anatomical structures and the references obtained by different incidences of fluoroscopy and the endocavitary electrocardiogram. But understanding the anatomy also requires a certain knowledge of dissection to determine, for example, the orientation of bundles of muscle fibres and anatomical sections. The sino-atrial node is situated at a distance from the endocardium. It is long and protected by its own artery which makes it difficult to reach. The atrio-ventricular node has multiple posterior expansions which correspond to the sites where radiofrequency ablation is effective. The cavo-tricuspid isthmus is the target zone for the treatment of atrial flutter but radiofrequency ablation which must be long may be applied at three different levels: inferolateral, median (the most common site) or inferoseptal. Finally, atrial fibrillation has incited many studies of the muscular extensions of the left atrium to the pulmonary veins, the morphological variations of these veins and the organisation of the muscle fibres of the left atrial wall. They have inspired new concepts of atrial fibrillation.
Farré
J
J
Servicio de cardiologia, Fundacion Jimenez Diaz, Madrid, Espagne. jfarre@telefonica.net
Cabrera
J A
JA
Sánchez-Quintana
D
D
Ho
S Yen
SY
Anderson
R H
RH
D001145:Arrhythmias, Cardiac / Q000473:pathology*; D001281:Atrial Fibrillation / Q000473:pathology / Q000601:surgery; D006325:Heart Atria / Q000033:anatomy & histology / Q000473:pathology*; D006801:Humans; D011667:Pulmonary Veins