Can Preoperative Measurement of Mid-regional Proadrenomedullin Predict Postoperative Organ Dysfunction and Mortality in Patients Undergoing Valvular Surgery?

Objectives: Systemic inflammatory response leading to multiple organ dysfunctions (MODS) is a major complication after cardiopulmonary bypass especially in patients with infective endocarditis (IE). Preoperative prediction of postoperative MODS is important. In patients with sepsis, mid-regional proadrenomedullin (MR-proADM) was shown to be more predictive for mortality or morbidity than procalcitonin (PCT) and C-reactive protein (CRP). Data investigating the prognostic value of MR-proADM in patients undergoing cardiac surgery using cardiopulmonary bypass are lacking.

Methods: We conducted a monocentric, prospective case–control diagnostic study comparing two groups of patients undergoing cardiac surgery for IE or for noninfectious valvular heart disease. We measured plasma profiles of several biomarkers including MR-proADM, PCT, and CRP at defined time points in all patients. We used sequential organ failure assessment (SOFA) score to evaluate organ dysfunction. The study is registered in the German Register of Clinical Studies, ID: NCT02727413.

Results: Between May and December 2016, we included 40 patients (20 per group). Mean age was 65.1 ± 9.9. Both groups showed similar distribution of age and gender.

In-hospital mortality was higher in IE patients (35 vs. 5%; p < 0.001). Incidence of postoperative organ dysfunction was higher in IE patients (SOFA 9.3 ± 3.2 vs. 6.6 ± 1.6, p = 0.014). In the whole study population, the mean level of preoperative MR-proADM was significantly higher in survivors compared with nonsurvivors (3.78 ± 3.1 vs. 1.44 ± 1.02, p = 0.002), independent of the presence of IE. Preoperative MR-proADM was the only marker that performed well in predicting mortality (area under the receiver operating curve =0.863). Correlation analysis showed that pre-operative MR-proADM correlated to SOFA score 24 hours after surgery (r = 0.622, p < 0.001), slightly higher than PCT and CRP (r = 0.483 and 0.573, p = 0.002 and < 0.001, respectively).

Conclusion: Our results suggest that MR-proADM can be used as a biomarker for early prediction of postoperative organ dysfunction and mortality. Therefore, MR-proADM may be added to the routine preoperative diagnostic in patients undergoing valvular cardiac surgery.

No conflict of interest has been declared by the author(s).