Successful treatment of symptomatic first-degree atrioventricular block after Occlutech Figulla Flex II atrial septal defect occluder placement.

Given the rarity of significant first-degree atrioventricular block (AVB) after Occlutech Figulla Flex II atrial septal defect occluder (OFF II, Occlutech International AB, Helsingborg, Sweden) placement, its management and predictors of recovery have not been established. We report a 9-year-old boy who developed significant first-degree AVB a day after OFF II deployment. Thereafter, oral prednisolone was initiated at 1.5 mg/kg/day. On day 2 of steroid treatment, normal sinus rhythm without conduction delays was occasionally observed, while the prolonged PR interval on the exercise stress test was ameliorated. After 5 days of steroid administration, normal sinus rhythm without conduction delays was completely achieved. An increase in the frequency of normal sinus rhythm and the absence of conduction delays on electrocardiogram monitoring and exercise stress test play an important role in predicting recovery from prolonged PR interval. Thus, steroid treatment can be effective and should be considered for patients who develop first-degree AVB after undergoing OFF II placement for transcatheter device closure of atrial septal defect. <Learning objective: Given the infrequency of atrioventricular block (AVB) after transcatheter device closure of atrial septal defect (ASD), its management remains unclear. To determine the management of and predictors of recovery from AVB after transcatheter closure of ASD, assessing the clinical course during recovery to normal sinus rhythm after steroid treatment is imperative.>.