Auto-antibodies against apolipoprotein A-1 and phosphorylcholine for diagnosis of non-ST-segment elevation myocardial infarction.
J Intern Med. 2011 Nov 7;
Authors: Keller PF, Pagano S, Roux-Lombard P, Sigaud P, Rutschmann OT, François M, Denis H, Vuilleumier N
Abstract
Objectives:? To explore the diagnostic accuracies of anti-apolipoproteinA-1 (anti-ApoA-1) IgG and anti-phosphorylcholine (anti-PC) IgM alone, expressed as a ratio (anti-ApoA-1 IgG/anti-PC IgM), and combined with the TIMI score for non-ST-segment elevation myocardial infarction (NSTEMI) (NSTEMI-TIMI score) to create a new diagnostic algorithm - the Clinical Autoantibody Ratio (CABR) score - for diagnosis of NSTEMI and subsequent cardiac troponin I (cTnI) elevation in patients with acute chest pain (ACP). Methods:? In this single-centre prospective study, 138 patients presented at the emergency department with ACP without ST-segment elevation myocardial infarction. Anti-ApoA-1 IgG and anti-PC IgM were assessed by enzyme-linked immunosorbent assay on admission. Post-hoc determination of the CABR score cut-off was performed by receiver operating characteristics analyses. Results:? The adjudicated final diagnosis was NSTEMI in 17% (24/138) of patients. Both auto-antibodies alone were found to be significant predictors of NSTEMI diagnosis, but the CABR score had the best diagnostic accuracy (area under the curve [AUC]: 0.88; 95% confidence interval [CI]: 0.82-0.95). At the optimal cut-off of 3.3, the CABR score negative predictive value (NPV) was 97% (95% CI: 90-99). Logistic regression analysis showed that a CABR score >3.3 increased the risk of subsequent NSTEMI diagnosis 19-fold (odds ratio: 18.7; 95% CI: 5.2-67.3). For subsequent cTnI positivity, only anti-ApoA-1 IgG and CABR score displayed adequate predictive accuracies with AUCs of 0.80 (95% CI: 0.68-0.91) and 0.82 (95% CI: 0.70-0.94), respectively; the NPVs were 95% (95% CI: 90-98) and 99% (95% CI: 94-100), respectively. Conclusion:? The CABR score, derived from adding the anti-ApoA-1 IgG/anti-PC IgM ratio to the NSTEMI-TIMI score, could be a useful measure to rule out NSTEMI in patients presenting with ACP at the emergency department without electrocardiographic changes.
PMID: 22061093 [PubMed - as supplied by publisher]