Anatomy of the left atrium for interventional echocardiography.

The anatomy of the left atrium is reviewed with relevance to various interventional transcatheter procedures requiring manoeuvres within or passage through the left atrium. The component parts of the atrium--the atrial body with a vestibule, appendage, venous component, and the atrial septum--are described with emphasis on their spatial relationships to neighbouring cardiac and extra-cardiac structures. Normal variations are discussed for a better understanding of the anatomy so as to reduce the risk of potential complications during procedures.