Neutrophil extracellular traps as a promising marker of poor prognosis in operated patients with infective endocarditisarditis.

Abstract

Aim. To assess the prognostic value of the formation of neutrophil extracellular traps (NETs) in blood smears of operated patients with infective endocarditis (IE).Material and methods. We prospectively included 46 patients with verified IE and 50 patients with valvular heart disease without IE, hospitalized in a cardiac surgery hospital in 2021-2022 (Moscow), comparable by sex and age. In all patients, NETs were determined upon admission and 7 days after surgery using the MECOS-Ts2 automated microscope (Russia). Patients included in the study were prospectively followed during the in-hospital period (ME [IQR] 30,0 [21,0-41,0] days) for the primary composite endpoint (in-hospital all-cause mortality, embolic, intracardiac, infectious complications) and its individual components.Results. Patients with IE were predominantly male (n=37, 80,4%) with a median age of 55,5 [44,0-70,0] years. The primary combined endpoint was recorded in 76,1% (n=35) of those examined with IE. The NET level after 7 days was significantly higher in patients with IE who had primary combined endpoint events than in the group of operated patients with heart defects without IE (Me [IQR] 4,4 [0,6-26,6] vs 2,9 [1,1-4,3], respectively, p<0,05). Patients with IE who died in the hospital had a significantly higher NET level compared with surviving patients with IE and the control group as at admission (9,2 [1,8-18,9] vs 4,2 [0,3-28 ,5] and 3,4 [1,76,9], respectively, p<0,05), and in dynamics (18,2 [5,2-26,6] vs 4,0 [1, 0-26,6] and 2,9 [1,1-4,3], respectively, p<0,001). The threshold value of dynamic NET ≥11,2% predicted in-hospital death with high accuracy (sensitivity 80,0%, specificity 90,0%, positive predictive value 66,7%, negative predictive value 100,0%, area under the curve 0,915, p=0,003) and the development of postoperative sepsis (sensitivity 75,0%, specificity 88,0%, positive predictive value 60,0%, negative predictive value 100,0%, area under the curve 0,884, p=0,01). The obtained cut-off values significantly predicted the death (OR 23,9 (95% CI 1,7-344,8, p=0,02)) and sepsis (OR 22,0 (95% CI 1,9-256,8, p=0,01)) in the hospital in operated patients with IE.Conclusion. The NET level in blood smears of operated patients with IE is a new promising marker for predicting the disease complicated course. NETs ≥11,2% in operated patients with IE increase the probability of hospital mortality by 24 times and postoperative sepsis by 22 times.