Author`s Reply.

To the Editor,

We really appreciate the interest in and comments for our article “A novel score in the prediction of rhythm outcome after ablation of atrial fibrillation: The SUCCESS score” (1). Firstly, we agree with the colleague’s opinion that remodeling of the left atrium (LA) is assessed more precisely using volume instead of diameter values. Even though the anteroposterior measurement is the most commonly used parameter in size assessment of LA, it does not consider the geometry. The recommendations of the American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI) state: “[…] this measurement has been used extensively in clinical practice and research, it has become clear that frequently it may not represent an accurate picture of LA size” (2). However, LA volume is not always routinely obtained in all patients, and it was unfortunately also the case in our retrospective study (1). EACVI furthermore states that 3D echocardiography, which is the most accurate form of volume measurement, “is poorly applied in the clinical practice because of the lack of standardized methodology and limited normative data. Although several studies demonstrated the incremental prognostic value of LA strain in diseases such as atrial fibrillation and mitral valve disease, the lack of a dedicated software and standardized methodology prevent its inclusion in a routine echocardiographic report” (3).

We fully agree with the colleague’s comment that the LA volume is superior for the risk assessment than the LA diameter; however, the latter is still used more commonly in clinical practice. The main goal of our study (1) was to create a simple scoring system using routinely obtained parameters, and therefore, it included diameter rather than volume. Further, it seems promising to apply a volume-based assessment of the LA size if this data is obtained more routinely in the future as recommended by both ASE and EACVI.