This is one of those cases where there are two hostas with the same name. Neither is registered with The American Hosta Society. The first one to be registered would become the "official" hosta of that name and the other would have to be renamed.

There is an image of this cultivar on the Hosta Library. From the (low quality) photo on the HL website, it appears to be a medium size hosta with dark green leaves and creamy white streaked and medial (center) variegation. This non-registered cultivar was originated in the Netherlands.

Hosta Helper will call this plant 'Silver Heart' (Unknown)

 

According to The Hostapedia by Mark Zilis (2009), "I've seen two distinctly different plants with white-centered foliage bear the same name. One...is the plant...on the Hosta Library. ..The other 'Silver Heart' is a Hosta sieboldii-type that is similar to 'Shiro Kabitan' (aka 'Haku-chu-han' and 'Silver Kabitan')..."

Hosta Helper will call this plant 'Silver Heart' (Sieboldii)