Predictors of acute inefficacy and the radiofrequency energy time required for cavotricuspid isthmus-dependent atrial flutter ablation Jordi Pérez-Rodon 1 & Julian Rodriguez-García 1 & Axel Sarrias-Merce 1 & Nuria Rivas-Gandara 1 & Ivo Roca-Luque 1 & Jaume Francisco-Pascual 1 & Alba Santos-Ortega 1 & Gabriel Martín-Sánchez 1 & Ignacio Ferreira-González 2 & Jose Rodríguez-Palomares 1 & Artur Evangelista-Masip 1 & David García-Dorado 1 & Àngel Moya-Mitjans 1 Received: 5 December 2016 /Accepted: 6 February 2017 # Springer Science+Business Media New York 2017 Abstract Purpose Although cavotricuspid isthmus-dependent atrial flutter (CTI-AFL) ablation is a highly efficacious treatment, a bidirectional CTI block cannot be achieved in some patients. In this study, we sought to determine the predictors of acute inefficacy of CTI-AFL ablation and the predictors of the ra- diofrequency (RF) energy time required to achieve a complete bidirectional CTI block. Methods All consecutive patients who underwent stand-alone CTI-AFL ablation in our institution, except patients with con- genital heart disease, were included in this retrospective study. Clinical, echocardiographic, and ablation data were collected from the Arrhythmia Unit and Imaging Unit databases and medical charts. Results Three hundred and fifty-five patients, with a mean age 63 ± 12 years, were included. The ablation was acutely ineffi- cacious in 30 patients (9%). Tricuspid regurgitation was the only independent predictor of acute inefficacy of CTI-AFL ablation (OR 3.161, 95% CI 1.084–9.220, p = 0.035) and was associated with a longer RF time required to achieve CTI bidirectional block (p = 0.031). Age was inversely correlated with the RF time required to achieve a bidirectional CTI block (r = -0.133, p = 0.025). A previous CTI RF abla- tion, chronic obstructive pulmonary disease (COPD), the use of an irrigated catheter, and advanced age were the indepen- dent predictors for requiring less RF energy time to achieve a bidirectional CTI block. Conclusions Tricuspid regurgitation is associated with less acute efficacy in CTI-AFL ablation. Prior CTI ablation, COPD, use of an irrigated catheter, and advanced age are independent predictors for needing less RF energy time to achieve a complete bidirectional CTI block. Keywords Ablation . Cavotricuspid isthmus-dependent atrial flutter . Efficacy . Predictors . Radiofrequency time Abbreviations AFL Atrial flutter COPD Chronic obstructive pulmonary disease CS Coronary sinus CTI Cavotricuspid isthmus CTI-AFL Cavotricuspid isthmus-dependent atrial flutter FEV 1 Forced expiratory volume in 1 s GOLD Global Initiative for Chronic Lung Disease LA Left atrium LVEDD Left ventricular end-diastolic diameter LVEF Left ventricular ejection fraction LVESD Left ventricular end-systolic diameter OSA Obstructive sleep apnea RA Right atrium RF Radiofrequency RV Right ventricle * Jordi Pérez-Rodon jordiperez@vhebron.net 1 Department of Cardiology, Hospital Universitari Vall d’Hebrón. Universitat Autònoma de Barcelona, Edifici Annexos, planta 9, Passeig Vall d’Hebrón, 119-129, 08035 Barcelona, Spain 2 Department of Cardiology, CIBER de Epidemiología y Salud Pública, CIBERESP, Hospital Universitari Vall d’Hebrón. Universitat Autònoma de Barcelona, Edifici Annexos, planta 9, Passeig Vall d’Hebrón, 119-129, 08035 Barcelona, Spain J Interv Card Electrophysiol DOI 10.1007/s10840-017-0232-z