Sirs:

We thank the authors for their important contribution. We briefly alluded to this pathophysiology in our discussion and regret that we have quoted the authors and not discussed this in more detail, simply because of constraints in space.

However, as the attached picture shows, the structure clearly protruded into the right atrial opening of the channel and was therefore not interpreted as a local thrombus formation. The different appearance of the right atrial opening before and after thrombus disappearance do underscore our interpretation.