Received: 16 October 2017 Accepted: 17 October 2017 DOI: 10.1111/jce.13393 LETTER TO THE EDITOR Incidence of left atrial thrombus prior to catheter ablation of atrial fibrillation: Is it time for atrial cardiomyopathy evaluation? To the Editor, We read with great interest the article by Gunawardene et al. 1 We would like to add some commentaries about the presence of left atrial thrombus in anticoagulated patients with atrial fibrillation (AF) before pulmonary vein isolation. In this recently published article, the authors concluded that: “Pre- procedural transesophageal echocardiography (TEE) may be dispensed in patients with a CHA2DS2-VASc score ≤1,” because “a cut off value for a CHA2DS2-VASc score of ≤1 has a 100% sensitivity for exclu- sion of left atrial appendage thrombus.” In some patients (“with an increase in the CHA2DS2-VASc score, a reduced LVEF of less than 30%, a history of nonparoxysmal AF, or presence of hypertrophic car- diomyopathy”), a “TEE should be performed leading to an individual- ized approach in this regard.” In another study of similar design, 2 the authors obtained an identi- cal result: A “CHA2DS2-VASc score < 2 has a maximal-negative predic- tive value for the presence of left atrial/left atrial appendage thrombi in anticoagulated patients with AF planned for pulmonary vein isolation.” In addition, left atrial appendage thrombi were significantly associated with persistent AF (P = 0.002), heart failure (P < 0.001), diabetes mel- litus (P = 0.017), spontaneous echo contrast (P < 0.001), and low left atrial appendage-peak emptying velocity (P < 0.001). Analyzing the literature quoted by Gunawardene et al. 1 (table 7), we remarked that in our study with 681 patients, we found almost the same prevalence of left atrial/left atrial appendage thrombi before AF ablation (1% vs. 0.78%). 2 Moreover, the most important thing is that in this population, we proposed an algorithm, making a distinction between paroxysmal and nonparoxysmal AF and the decision not to perform a TEE was restricted to patients without heart disease. 2 In these patients, the presence of left atrial/left atrial appendage seems to be not depending on an appropriate anticoagulation level 3 or anticoagulation treatment type (with vitamin K or nonvitamin K antagonists), 1 neither of clinical risk factors 4 as CHA2DS2-VASc scores ≥2; history of nonparoxysmal AF; chronic heart failure, as well as nonclinical ones like 4 : dilated left atrium; hypertrophic cardiomy- opathy; left atrial appendage morphology (≥3 left atrial appendage lobes), or the presence of sinus rhythm at the time of TEE. We agree that “an individual risk stratification on preablation TEE should be conducted for each patient prior to AF ablation, instead of making a generalized statement on whether preablation TEE is dis- pensable or not in all patients undergoing AF ablation.” Probably, it is time for an individualized approach in every patient with AF, appropri- ate anticoagulated or not, because left atrial fibrosis is the key. Hyper- coagulability causes atrial fibrosis and promotes AF 5 due to throm- bogenic fibrotic atrial cardiomyopathy occurrence 6 ; left atrial fibrosis induced by structural remodeling is associated with stroke risk. 7 This vicious circle should be analyzed in each patient. Therefore, probably, it is time for atrial cardiomyopathy evaluation to understand the incidence of left atrial thrombus prior to catheter ablation of AF. ORCID Mariana Floria MD, PhD http://orcid.org/0000-0002-9465-1503 Olivier Xhaet MD http://orcid.org/0000-0002-4133-0191 Mariana Floria MD, PhD 1,2 Dominique Blommaert MD 1 Olivier Deceuninck MD 1 Olivier Xhaet MD 1 Luc De Roy MD 1 1 “Sf. Spiridon” Emergency Hospital, University of Medicine and Pharmacy “Grigore T. Popa,” Iasi, Romania 2 Department of Cardiology, CHU of Mont-Godinne, Universitè catolique de Louvain, Yvoir, Belgium REFERENCES 1. Gunawardene M, Dickow J, Schaeffer BN, et al. Risk stratification of patients with left atrial appendage thrombus prior to catheter ablation of atrial fibrillation: An approach towards an individualized use of transesophageal echocardiography. J Cardiovasc Electrophysiol. 2017;28:1127–1136. 2. Floria M, De Roy L, Xhaet O, et al. Predictive value of thromboembolic risk scores before an atrial fibrillation ablation procedure. J Cardiovasc Electrophysiol. 2013;24:139–145. 3. Zhu WG, Xiong QM, Hong K. Meta-analysis of CHADS2 versus CHA2DS2-VASc for predicting stroke and thromboembolism in atrial fibrillation patients independent of anticoagulation. Tex Heart Inst J. 2015;42:6–15. 4. Laish-Farkash A, Suleiman M. Evaluation of left atrial thrombus prior to catheter ablation of atrial fibrillation: Is it time for an individualized approach? J Cardiovasc Electrophysiol. 2017;28:1137–1139. 5. Spronk HM, De Jong AM, Verheule S, et al. Hypercoagulability causes atrial fibrosis and promotes atrial fibrillation. Eur Heart J. 2017;38: 38–50. 6. Hirsh BJ, Copeland-Halperin RS, Halperin JL. Fibrotic atrial car- diomyopathy, atrial fibrillation, and thromboembolism: Mechanis- tic links and clinical inferences. J Am Coll Cardiol. 2015;65:2239– 2251. 7. Daccarett M, Badger TJ, Akoum N, et al. Association of left atrial fibro- sis detected by delayedenhancement magnetic resonance imaging and the risk of stroke in patients with atrial fibrillation. J Am Coll Cardiol. 2011;57:831–838. J Cardiovasc Electrophysiol. 2017;1. c  2017 Wiley Periodicals, Inc. 1 wileyonlinelibrary.com/journal/jce