Inflammatory Mediator Profiles During Heart Valve Replacement Surgery

Exaggerated release of inflammatory mediators and endogenous vasoactive substances resulting from the coincident infection and surgical stress plays a role in post-operative organ failure and altered immune defense, thus contributing to unfavorable post-operative outcome. Cardiopulmonary bypass (CPB) itself, even in the absence of IE, has been shown to modify cytokine and vasoactive mediator release and may cause organ failure. Tracing of release profiles of inflammatory cytokines and vasoactive mediators and their correlation with postoperative organ dysfunction in cardiac surgery for IE or non-IE patients aims at the assessment of the prognostic validity of these biomarkers and the evaluation of measures for their pro-active clearance during the surgical intervention. Induction of inflammatory mediators and their temporal release profile may vary depending on the involved pathogens, which cannot be always identified by conventional techniques (blood culture). Since it is conceivable that identification of the involved pathogen could explain differences in cytokine secretory patterns in IE, use of advanced molecular technologies (NGS) will support the clarification of such relations. Analysis of transcripts encoding inflammatory and vasoactive mediators in blood cells will enable the surveillance of temporal oscillations in their profiles during the observation time frame. Transcriptome analysis of identified putative pathogens can also disclose features of antibiotic resistance.