Resolution of right heart enlargement after closure of secundum atrial septal defect with transcatheter technique

OBJECTIVES The purpose of this study was to prospectively characterize the reduction in right atrial (RA) area and right ventricular (RV) volume after transcatheter closure of atrial septal defect (ASD) and to investigate fac tors that may predict magnitude of resolution in right heart enlargement. BACKGROUND Secundum ASD can cause volume overload of the right side of the heart with the Potential for development of late complications. Little is k nown about reduction in right heart size after closure of ASD. METHODS Transthoracic echocardiography was performed in 38 patients undergo ing transcatheter closure of ASD. The RA area and RV volume were measured p rior (n = 38), within 24 hours (n = 37), at 3 to 6 months (n = 24), at 12 m onths (n = 20) and at 24 months (n = 10) after closure of ASD. Change over time within the study group was assessed and the study group was compared t o a control group of 19 patients with structurally normal hearts. RESULTS Indexed RA area decreased from baseline to 3- to 6-month follow-up (p = 0.004) as did indexed RV volume (p < 0.0001). Indexed RV volume was si milar to that in the control group at 24 months (p = 0.3); however, indexed RA area remained greater than in the control group (p = 0.006). Decrease i n indexed RA area over the first 12 months of follow-up was related to youn g age at time of closure by regression analysis (r = 0.55, p = 0.013). CONCLUSION Closure of secundum ASD results ill decreased indexed RV volume comparable to that ill control subjects at 24 months following closure. Ind exed RA area remains increased compared to that in control subjects but doe s decrease over time. Decrease ill RA area is inversely proportional to age at time of ASD closure. Long-term follow-up is required to evaluate the cl inical impact of persistently increased RA size. (J Am Coll Cardiol 2001;38 :1528-32) (C) 2001 by the American College of Cardiology.