1Universitätsklinikum Regensburg Klinik und Poliklinik für Innere Med. II, Kardiologie Regensburg, Deutschland
Aims: It is already known that N-terminal pro B-type natriuretic peptide (NT-proBNP) measured in acute coronary syndrome (ACS) independently predicts mortality and adverse cardiac events. The goal of this study was to evaluate the prognostic value of biologically active adrenomedullin (bio-ADM) compared to NT-proBNP in patients presenting with acute chest pain as well as in the subgroup of patients with ACS in the emergency department.
Methods and results: Bio-ADM and NT-proBNP were measured at admission in 341 patients with acute chest pain. In the current analysis, 197 patients suffered from ACS. A follow-up (median of 55 months) was performed in regard to all-cause mortality as well as combined endpoint of major adverse cardiac events (all-cause mortality, ACS with the necessity of a coronary intervention, congestive heart failure, and stroke/transient ischaemic attack; MACE). 60 patients died during follow-up and 108 reached the combined endpoint. Bio-ADM and NT-proBNP correlated positively and significantly (r = 0.465, p < 0.05). Additionally, the concentrations of both biomarkers were significantly elevated in patients with troponin positive ACS as well as unstable angina pectoris compared to patients with chest wall syndrome (each p < 0.05). Moreover, deceased patients as well as patients with MACE showed significant higher concentrations of bio-ADM and NT-proBNP. Regarding ROC analysis, both markers showed very satisfying area under the curve (AUC) values for all-cause mortality and MACE (all-cause mortality: AUCbio-ADM 0.76, AUCNT-proBNP 0.82; MACE: AUCbio-ADM 0.72, AUCNT-proBNP 0.76). Both biomarkers presented still satisfying AUC values for all-cause mortality and MACE in the ACS cohort. There were no significant differences between the AUCs for bio-ADM and NT-proBNP in each case (p = n. s.). Regarding Kaplan-Meier analysis, bio-ADM and NT-proBNP were each a significant predictor for all-cause mortality and MACE in the overall study cohort as well as in the subgroup of patients with ACS (each p < 0.05). In accordance with Cox regression analysis, bio-ADM and NT-proBNP were significant and independent predictors for all-cause mortality in total study cohort and ACS subgroup (each p < 0.05). With a combination of the two biomarkers the event rate for both endpoints increased in comparison to NT-proBNP or bio-ADM alone (each p < 0.05).
Conclusions: In addition to NT-proBNP, bio-ADM seems to provide a significant predictive value in a long-term follow-up in patients with acute chest pain and patients with ACS regarding the endpoints all-cause mortality and major adverse cardiac events.