To the Editor,
First of all, we would like to thank Dr García Cosío and coworkers for the highly constructive critique that they have made of our article. Undoubtedly, their comments are correct with regard to the diagnostic accuracy of the technique: other imaging techniques such as magnetic resonance and computed tomography are much more suitable when it comes to defining the anatomy of left atrium and it is true that the software employed in the study is designed, as mentioned in the article, for the evaluation of the volume of left ventricle.1
However, we would like to clarify a series of points. First, one of the objectives of this study is to define the values using this specific technique. Undoubtedly, they are not the most accurate ones,2,3 but a) the echocardiogram is a technique that is infinitely more accessible to the patient than cardiac magnetic resonance or computed tomography; b) the echocardiogram is a portable technique and, thus, the evaluation can be carried out in different clinical settings, not only, like the other techniques, in a radiology unit; and c) in contrast to computed tomography, the echocardiogram does not emit ionizing radiation. On the other hand, based on our own experience, with the changes introduced when it comes to applying the software for left ventricle for measuring the volumes of left atrium, the follow-up of the left atrial wall carried out by the system throughout the cardiac cycle is correct.
In conclusion, we can say that the objective of our paper was not to compare the echocardiogram with other imaging techniques, which, indisputably, are more suitable for the evaluation of left atrium, but to demonstrate the normal values for left atrium when evaluated with 3D-echocardiography using software designed for left ventricle but applied to the left atrium. There can be no doubt that 3D-echocardiography provides a new, accessible possibility for the study of the atrium, with its advantages and its limitations.