Dear Editor, We read with great interest the article recently published in Journal of Cardiovascular Electrophysiology, “Left atrial appendage dimension predicts elevated brain natriuretic peptide in nonvalvular atrial fibrillation” by Cook JA. et al. 1 The authors have studied the relation between Brain natriuretic peptide (BNP) elevations and left atrial appendage measurements in patients who referred for left atrial appendage (LAA) occlusion in patients with nonvalvular atrial fibrillation (AF). BNP release is largely from the ventricles and it is also dynamically dependent on myocardial stretch and fluid volume status. However, it seems difficult to prove that BNP levels are directly related to the LAA measurements. Correlating BNP elevation only with left atrial or LAA measurements means ignoring left ventricular strain. Considering that these patients were referred for LAA occlusion and had a high CHA 2DS 2-VASc score, and not taking heart failure with preserved ejection fraction into account may lead to errors in interpreting the results. Moreover, it should be evaluated that the left atrial appendage may undergo remodeling or enlargement as a result of the left ventricular end-diastolic pressure increase. In this case, although the study is valuable, remains a cross-sectional study and a snapshot of the correlation of BNP and LAA. Second, it should be disclosed whether patients have paroxysmal or chronic AF and how long the patient has had AF. A relationship was established between LAA dimensions and BNP in the study, it is essential that the duration of AF should be considered and subgroup analyses should be evaluated if possible, since AF has a significant effect on BNP release. We appreciate this study and believe that a more detailed evaluation including left ventricular evaluation and prospectively monitored LAA and BNP would yield more realistic results. In addition, we think that it would be useful to evaluate midregional pro-A-type natriuretic (MR-proANP) in LAA studies, which is specific to the left atrial enlargement and similar physiology to BNP. 2

We have read with great interest the article “Efficacy of Catheter Ablation for Premature Ventricular Contractions (PVC) in Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)” by Assis F.R. et. al. PVC ablation in ARVC was previously studied by Aras D. et al and they presented successful results.In this study, we believe that the study should not be considered as unsuccessful since 2 patients showed a decrease in PVC burden by more than 80% and in the other three patients between 45-70%. The demonstration of a decrease in PVC burden with catheter ablation in ARVD patients indicates that a second ablation may increase the success rate and decrease symptoms. The fact that ARVC has a complex substrate and the disease can progress is undoubtedly the most important factor in achieving the desired success with PVC ablation. Epicardial ablation with endocardial ablation has increased the chance of success in this patient group. In addition, given that BCSD ablation and basal heart rate are guaranteed by ICD implantation, we think that administration of the maximum dose of antiarrhythmic medication may create a significant improvement in these patients. And another factor, contact force sensing plays an important role in evaluating the effectiveness of the process. We suggest that with the current treatment modalities, a pharmacoablative combination therapy and re-ablation when necessary would be appropriate for such a complicated disease.