抄録
Background: Patients after open-heart surgery may develop macroreentrant atrial flutter (AFL) related to the right atriotomy scar (incisional AFL; I-AFL), which occasionally forms a dual-loop reentry circuit with cavotricuspid-isthmus dependent AFL (CTI-AFL). Objective: To demonstrate the prevalence and characteristics of dual-loop reentrant AFL (DL-AFL) consisting of I-AFL and CTI-AFL after open-heart surgery. Methods and Results: Thirty-six consecutive patients (25 males, 61±13 years) with I-AFL (n=6), CTI-AFL (n=22), or both AFLs (n=8) who underwent radiofrequency catheter ablation were retrospectively studied. Four of the 8 patients with both AFLs had a DL-AFL. In all patients with DL-AFL, CTI-AFL was clinically predominant and had a shorter flutter cycle length than I-AFL (260±37 ms vs. 281±35 ms). The flutter wave polarities in the inferior leads and lead V1 on the 12-lead electrocardiogram were negative and positive in 2 patients, negative and negative in 1, and positive and positive in 1, respectively. Conclusion: DL-AFL occurred in 14% of the patients with macroreentrant right atrial flutter after open-heart surgery and had variation in the flutter wave morphology. Thus, entrainment mapping and three-dimensional electroanatomic mapping can help to identify and localize the reentry circuits and critical isthmuses as targets for ablation.
