Abstract

The right atrium has a significantly higher capacitance than the left atrium, and this may affect the Doppler flow pattern across an atrial septal defect (ASD) in unilateral atrioventricular (AV) valve atresia. This Doppler flow pattern is often used to assess ASD adequacy in this setting. We studied the effect of atrial capacitance and ASD size on the trans-ASD Doppler flow pattern in an in vivo flow model of alternate left or right AV valve atresia (LAVVA and RAVVA). We assessed trans-ASD Doppler flow patterns using the max/min velocity ratio and mean interatrial pressure gradients (PGs). In both models, ASD flow rate correlated with mean trans-ASD PG, but for similar flow rates the slope was higher in the LAVVA model. In LAVVA, a persistent PG was consistently observed, with low max/min ratio (median, 1.46; range, 1.03-3.13), whereas in RAVVA, phasic flow was common (median, 8.0; range, 2.8-20). Because atrial capacitance affects mean PG and Doppler flow pattern across the ASD, we propose that the assessment of ASD adequacy in RAVVA should not rely on Doppler findings.

View details for DOI 10.1016/j.echo.2004.07.015

View details for Web of Science ID 000225590900012

View details for PubMedID 15562268