0246

THE CHANGES OF RIGHT VENTRICULAR VOLUME LOAD AFTER CATHETER CLOSURE OF ATRIAL SEPTAL DEFECTS

Du Z-D^1,2, Cao Q-L¹, Koenig PR¹, Waight DJ¹, Hijazi ZM¹

¹ University of Chicago, Chicago, Illinois, USA

² Capital Institute of Pediatrics, Beijing, China

Objectives: Abnormal ventricular septal (IVS) motion often persist after surgical repair of atrial septal defect (ASD). This study sought to evaluate changes of right ventricular volume over load after catheter closure of ASD using an Amplatzer septal occluder (ASO).

Methods: Echocardiography (ECHO) was performed on 42 consecutive patients (M/F 14/28, age 3.3-84 years) with isolated ASDs before, 24 hours and 6 months after catheter closure using an ASO. M-mode and 2-D ECHO were used to measure and assess the right atrial and right ventricular dimensions (RVD) and IVS motion. IVS motion was classified into paradoxical, flat and normal motion.

Results: Of 42 patients, 37 had singular ASDs of 16.6±6.8 mm (range 4 to 30 mm), 5 had multiple defects. Forty-four devices were successfully deployed. Complete closure rate was 88% immediately, 93% at 24 hrs, and 94% at 6 months after closure. RVD decreased from 30.8±8.5 mm before closure to 24.3±7.4 mm at 24 hours, and 16.4±6.1 mm at 6 months after closure (P<0.001). Right atrial major and minor axis also decreased significantly from pre-closure to 24 hrs after closure, but no significant changes occurred afterward. Paradoxical or flat IVS motion was identified in 95% patients before ASD closure, in 26% at 24 hours and 12% at 6 months after closure (P<0.01). By multiple regression, the change of RVD was related to RVD and pulmonary systolic pressure before closure and patient’s age.

Conclusion: Transcatheter closure of ASD by an ASO results in rapid normalization of right ventricular overload. Catheter closure is an effective therapy of secundum ASD in children and adults.