These results show that there can be significant variation in estimated flow volume depending on the position across the valve at which the data was acquired. This would have a significant impact on any subsequent interventional decisions.

The mean antegrade flow volume variation was 11.2 ml (13.1% of mean ategrade flow). Mean retrograde flow volume variation was 7.1 ml (33% of mean retrograde flow). 

The mean variation in regurgitant fraction was 7.4%.  

The data did not show a significant correlation between the subjective estimated severity of turbulence and the degree of variation of flow volumes. This may have been the result of the small cohort size. In addition, intraobserver variability was not assessed in this study. The results also raise the question as to whether turbulence can be reliably graded with subjective visual assessment.