A Simple Score to Predict New-Onset Atrial Fibrillation After Ablation of Typical Atrial Flutter

Background: New-onset atrial fi brillation (NeAF) is common after cavotricuspid isthmus-dependent counterclockwise atrial fl utter (CCWAFL) ablation. This study aimed to investigate a simple predictive model of NeAF after CCW-AFL ablation. Methods: From January 2013, to December 2017, consecutive patients receiving CCW-AFL ablation were enrolled from 3 centres. Clinical, echocardiographic, and electrocardiographic data were collected and followed. Patients from 2 centres and another centre were assigned into the derivation and validation cohorts, respectively. In the derivation cohort, logistic regression was performed to evaluate the ability of parameters to discriminate those with and without NeAF. A score system was developed and then validated. Results: Two hundred seventy-one patients (mean 59.7 f 13.6 age; 205 male) were analyzed. During follow-up (73.0 f 6.5 months), 107 patients (39.5%) had NeAF; 190 and 81 patients were detected in the derivation and validation cohorts, respectively. Hypertension, age > 70 years, left atrial diameter > 42 mm, P-wave duration > 120 ms and the negative component of fl utter wave in lead II > 120 ms were selected as the fi nal parameters. A weighted score was used to develop the HAD-AF score ranging from 0 to 9. In the derivation cohort, area under the receiver operating characteristic curve (AUC) was 0.938 (95% confidence fi dence interval [CI], 0.902-0.974), superior to those of currently used CHA2DS2-VASC 2 DS 2-VAS C (0.679, 95% CI, 0.600-0.757) and HATCH scores (0.651, 95% CI, 0.571-0.730) (P P < 0.001). Performance maintained in the validation cohort. Conclusions: Six years after CCW-AFL ablation, 39.5% of patients developed NeAF. HAD-AF score can reliably identify patients likely to develop NeAF after CCW-AFL ablation.