Patients with possible and definite IE had a similar risk of death.

In conclusion, unselected patients with possible IE (Duke criteria) had a similar prognosis than those with definite IE.

Patients with definite IE and those with possible IE who did not undergo surgery had a worse prognosis than their counterparts with surgery.

Results: From July 2007 to October 2010, 658 consecutive cases with definite IE according to Duke criteria have been enrolled in the RIEI (483 males).