Limitations
Due to the study’s retrospective design, there was a limitation in the number of
exams evaluated by Core Lab; however, the number was considered significant
(approximately 80%). Another limitation is that a control group was not
included. It is tough to include a “gold standard” control group in studies of
AVR and MVR, since market valves have particularities and limitations, thus, the
best alternative was to use OPC recommended by Annex J (ISO 5840-2), which
defines the reference standard for surgically implanted heart valve
substitutes