Venous flow patterns after percutaneous atrial septal defect closure: Does the mechanical device decrease right atrial compliance?

Abstract

Systemic venous flow patterns become abnormal and restrictive after surgical closure of ostium secundum atrial septal defect (ASD) but rarely studied after percutaneous device closure. From January 2017 to January 2018, systemic venous Doppler flow patterns were documented prospectively in 50 subjects who underwent percutaneous closure of ASD, prior to, after procedure, and at 6-month follow-up and correlated with defect size and device size. In hepatic veins and superior venacava post device-closure closure, the velocity time integral (VTI) of forward flow in both systole (S) and diastole (D) increased. Overall S was higher than D, and D/S ratio was <1. The D/S ratio increased after device closure significantly reflecting that the improvement in atrial filling increase in diastolic flow more than the increase in systolic flow. Increase in flow velocities was more prominent at 6months with further increase in D/S VTI ratios. When correlated with the defect size, in those with defect size less than 15mm/sq.m (mean device size 13.05±3.21mm), the changes in S- or D-wave, D/S ratio were less prominent and statistically not significant, while in subjects with defect size≥15mm/sq.m (mean device size 23.02 (±4.77mm), these changes were greater and statistical significant. Residual filling defects with restriction of systolic venous flow were observed in subjects after device closure, correlating with larger device sizes, implying the compliance abnormality conferred by them which progresses at 6months. Subjects with persistent abnormalities would need careful follow up for incomplete remodeling and increase in atrial size related arrhythmias.