CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 3, May/June 2022 116 AFRICA control. For patients with persistent AF, a more aggressive atrial substrate modification may be required. Available data in the published literature regarding the acute response to AADs for cardioversion after PVI and AA recurrence are limited. Our study demonstrated that the response to ibutilide after PVI could predict AA recurrence in patients with non-paroxysmal AF. As mentioned, the response to ibutilide was associated with the extent of atrial remodelling, which may in turn explain AF recurrence. Although the response to ibutilide was associated with the duration of AF, multivariate Cox analysis showed that the response to ibutilide was associated with AA recurrence, not AF duration. Hence, the response to ibutilide may be more reflective of AF progression than AF duration. Based on the predictive value of AF recurrence, the response to ibutilide during CA may help select patients with high risk of AA recurrence for more frequent post-ablation surveillance, contribute in the prediction of more accurate prognoses, and aid in the decision-making about anti-arrhythmic and anticoagulation therapies. Limitations This study has several limitations. First, this was a retrospective observational study in a single centre. All patients had a relatively small left atrial diameter. Therefore, a selection bias exists. Second, ibutilide administration was performed after successful PVI. Hence, the risk stratification after PVI is of limited clinical relevance. However, given its relationship with the long-term outcome, the response to ibutilide may guide intraprocedural ablation and post-ablation management. Third, as left atrial voltage mapping in the SR was not performed, we were unable to assess directly the relationship between the efficacy of ibutilide in AF termination and the size of the atrial low-voltage areas. In future studies, methods for evaluating atrial fibrosis, including intracardiac electro-anatomical mapping and cardiac magnetic resonance, should be combined with those evaluating the efficacy of ibutilide in AF termination. Finally, as some patients with asymptomatic AF may have been ignored during the follow up, we may have underestimated the rate of AA recurrence. Longterm monitoring of an implanted electrocardiogram may help resolve this problem. Conclusion Ibutilide (1 mg) for AF termination after PVI was effective in patients with non-paroxysmal AF. The response to intraprocedural ibutilide could predict AA recurrence after CA, which may be useful for risk stratification of AF recurrence and individualised AF management. 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