Atrioventricular block: a serious complication in and after transcatheter closure of perimembranous ventricular septal defects.

BACKGROUND: Transcatheter closure is an effective approach for perimembranous ventricular septal defects (PMVSD). However, atrioventricular blocks (AVB) emerged possibly due to the close proximity of the PMVSD to the conduction system, but concern for the complication was not adequately emphasized. In this study, we report the incidence of AVBs, in and after transcatheter closure of a PMVSD, and the outcome of the complication in our center.

METHODS: One hundred and sixty-eight PMVSD patients were accepted for transcatheter closure with Amplazter PMVSD occluder (AGA Medical, Plymouth, Minn., USA). The procedure was discontinued when a second- or third-degree AVB occurred. A steroid was administered to all patients who developed AVBs. Temporary pacemakers were inserted in patients who developed a complete AVB or Mobitz type II AVB during or after the procedure.

RESULTS: During the follow-up period of 6-24 mo (mean 10.6 +/- 3.9), the incidence of AVBs occurring during or after transcatheter closure of PMVSD was 3.5%. The AVB disappeared quickly after discontinuing the procedure in patients who developed AVBs during the procedure, whereas the AVBs disappeared between 2 and 21 d (mean 8.0 +/- 8.8) in the patients who developed AVBs after the procedure. However, complete right bundle branch block (CRBBB) was observed, and a transient complete AVB emerged after 8 mo in 1 case, incomplete right bundle branch block (IRBBB) in 1 case, and CRBBB and left anterior hemiblock (LAH) in 1 case.

CONCLUSIONS: The AVB is a serious complication during and after transcathter closure of PMVSD. More attention should be paid to the complication, and multicentres are required to monitor the complication.