Gross specimen evaluation
Gross examination of the regions of injection was undertaken by first
dissecting out the entire transmural region where ablation was
performed. We then did two orthogonal incisions through the center of
the lesion region to be able to evaluate the myocardium throughout the
ablated region. Presence of the conductive hydrogel was based on the
gross appearance throughout the region given that the black appearance
of the hydrogel is otherwise obvious against the surrounding myocardial
tissue. No specific quantification was done of the amount of hydrogel
retained within the volume of ablated tissue.