The Ir indicator and its modification Im in patients operated on for infective endocarditis – usefulness in operative risk prognosis and postoperative therapy assessment

Introduction: Anemia is a part of the endocarditis clinical presentation. C-reactive protein is one of the widely available inflammatory markers, which contributes to the diagnostic and prognostic process of infective endocarditis (IE). Both mentioned parameters are connected by the newly proposed risk indicator Ir.

The aim of the study was to assess its usefulness in patients subjected to cardiac surgery due to IE. We also evaluated the clinical application of the modified risk indicator Im.

Material and methods: The study involved 29 patients operated on for IE in the Cardiosurgical Clinic in Lodz. All laboratory examinations (CRP, RBC, Hb) and proper calculations were carried out: preoperatively, on the 3^rd, 7^th, 12^th and 21^st postoperative day. Patients were divided into 2 groups: without (A) or with (B) complications. The end points of prognostic significance were: decease, respiratory or circulatory failure over 72 h, the time of hospitalization and stay in the intensive care unit (ICU).

Results: Postoperative complications were found in 17 (58.62%) patients. A statistically significant increase of Ir and Im was observed on the 3^rd postoperative day (the highest values for the non-complicated group). The peak increase was noted on the 7^th day in the group with complications. The risk indicators began to decrease earlier in group A. The blood parameters decreased significantly on the 3^rd day and started to elevate significantly from the 12^th day. The perioperative mortality reached 10.34% (3) of patients.

Conclusions: The prognostic value for postoperative complications was proved for Ir and Im. Their superiority to CRP was found.