HL7 (Health Level-7) is application layer, which is "layer 7" in the OSI model. And It is set of multiple international standards.it not clear what you trying to achieve with Service Virtualization (what services to virtualized).
Please elaborate more so that we can understand what Devtest can do for you.
On side note: If we have any services which need to virtualize or API need to bypass. you may need to place those jar/library in Devtest hot deploy folder and try to work on SV.
With Devtest we can always go for extending/ implementing new features using LISA SDK.
Thanks,
Rajesh k Singh