Prediction of sinus node dysfunction in patients with persistent atrial flutter using the flutter cycle length

Aims Sinus node dysfunction (SND) occasionally coexists with atrial flutter (AFL). However, the identification of SND during AFL is difficult. We investigated whether we could predict underlying SND in patients with persistent AFL using the flutter cycle length (FCL). Methods and results We retrospectively studied 211 successfully ablated patients with persistent cavotricuspid isthmus (CTI)-dependent AFL and measured the FCL before the ablation and corrected sinus node recovery time (CSNRT) after the ablation. Twenty-four patients (11) required a permanent pacemaker implantation (PMI) for significant SND after AFL termination and had a longer FCL (295 37 vs. 236 34 ms; P 0.0001) and greater CSNRT (1727 1014 vs. 603 733 ms; P 0.0001) than those not requiring a PMI. A receiver-operating characteristic curve identified an FCL of 273 ms as the optimal cut-off value for predicting SND requiring a PMI (area under the curve 0.91; sensitivity, 83 and specificity, 89; P 0.0001). Multiple linear and logistic regression analyses revealed that the left ventricular ejection fraction (LVEF) ( 0.2; P 0.0016) and FCL ( 0.46; P 0.0001) were independently associated with the CSNRT, and that females [odds ratio (OR), 2.43; 95 confidence interval (CI), 1.324.62; P 0.0046], an LVEF 50 (OR, 2.10; 95 CI, 1.203.87; P 0.012), and an FCL of 273 ms (OR, 5.34; 95 CI, 3.0810.08; P 0.0001) were independent predictors of SND requiring a PMI. Conclusion Although this study was based on a review of a database, the results suggest that assessing the FCL in patients with persistent CTI-dependent AFL could be helpful in the risk stratification of underlying SND.