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Assessment of left atrial anatomy and function Symposium
Dr. Bogdan Alexandru Popescu
Session number: 940000
Session title: Assessment of left atrial anatomy and function
Authors: Popescu, B.A. Bucharest, Romania
Studies highlighting the prognostic role of left atrial (LA) size in various cardiovascular diseases and the introduction of newer interventional techniques involving the LA have increased the interest in a more detailed assessment of LA anatomy and function.
The first speaker of this Symposium, Dr. Yoram Agmon (Haifa, Israel) gave a detailed overview of LA physiology and of different methods used to assess LA function. Although we have the tools to assess LA function data about the incremental prognostic and therapeutic value of evaluating LA function over simply measuring LA size are still awaited. Further validation studies of LA function indices are needed, including establishing normal ranges.
Dr. Wael Jaber (Cleveland, USA) discussed the potential role of 3-D echo in assessing LA and LA appendage (LAA) function. He concluded that especially due to the very high accuracy of 2-D TEE (still the gold standard in LAA assessment), there seems to be no clear role for 3D echo in LAA assessment in clinical practice. The role of 3-D TEE might however increase with the increasing number of interventional procedures meant to occlude the LAA, but this remains to be proven.
Dr. Fabrice Bauer (Rouen, France) discussed the role of Tissue Doppler/strain imaging in assessing LA function. He showed that TDI interrogation of the LA is feasible. However, care must be taken in measuring LA tissue velocities and strain. Similarly to the left ventricle, LA myocardial displacement is dependent on multiple intrinsic and extrinsic parameters (among which age and heart rate), which have to be taken into account when interpreting the acquired data.
Prof. Lale Tokgozoglu (Ankara, Turkey) discussed the role of strain/strain rate imaging for diagnosing LAA stunning after cardioversion. She showed that strain/strain rate imaging is feasible for quantitation of longitudinal LA deformation, relatively independent from global cardiac motion. It can predict cardioversion success as well as maintainance of sinus rhythm. Among the main limitations are influence by loading conditions, angle dependency, and image quality (noise), which may raise difficulties.
Dr. Vesa Jarvinen (Hyvinkaa, Finland) spoke about the role of MRI in atrial and pulmonary venous anatomy and function assessment. MRI represents the validated standard for LA volumetry. LA size assessment by 2D echocardiography constantly underestimates LA volume, as assessed by MRI. Moreover, MRI allows an accurate assessment of the pulmonary veins, which becomes particularly important with the growing number of atrial fibrillation ablation procedures.
Conclusion
LA size is easy to measure and has strong prognostic data from large-scale studies. LA function assessment is more elusive. Data about its clinical relevance come from smaller studies and so far are less robust than data for LA size assessment. TDI/strain imaging are increasingly used for the study of LA function, but larger studies demonstrating its superiority over more conventional echo techniques are needed.
MRI is the gold standard for volumetric assessment of the LA, but due to issues of availability and cost, echocardiography remains the most widely used technique, validated and with an established prognostic role. For techniques using geometrical models in LA size assessment, LA shape probably deserves more attention than it has received, since this could allow more accurate measurements of LA size.
The content of this article reflects the personal opinion of the
author/s and is not necessarily the official position of the
European Society of Cardiology.
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