Figure 3

The three pulmonary flow curves in a typical case are shown above. In this individual, the pulmonary regurgitant fraction was 57% in held inspiration (left), 38% in held expiration (middle) and 53% during non-breath-hold acquisition (right). Late-diastolic forward flow, coinciding with atrial systole, is seen as positive flow at the right hand end of each curve in this case.