Abstract 17235: Midregional Pro-A-Type Natriuretic Peptide as Part of a Dual Biomarker Strategy for the Early Rule Out of Non-ST Segment Myocardial Infarction - WilCop Study
Purpose: MR-pro-ANP is produced in atrial, and in the states of extensive left ventricular overload,in left ventricular myocardium. Accordingly, plasma levels of ANP are elevated in patients with acute myocardial infarction and are strong predictors of mortality independent of troponin levels. We have investigated the effect of combined measurement of MR-pro-ANP and hs-cTnI levels for early identification of pats. with NSTEMI.
Methods: This was a prospective single-centre study of consecutive pats. admitted to our ED with chest pain suggestive of ACS. We included a total of 343 pats. All pats. had baseline MR-proANP and hs-cTnI measurements. Cutoff for MR-pro-ANP was set at its median (86.1 pmol/L; IQR=113.8) and for hs-cTnI at 56ng/L (99th percentile).
Results: In total, 31/343 (9.1%) pats. had an angiography-proven diagnosis of NSTEMI with median GRACE score of 96 (IQR=55). Levels of MR-pro-ANP at admission were significantly higher among pats. with proven NSTEMI then in pats. with non-AMI diagnosis (206 pmol/L (IQR=191.5) vs. 77.3pmol/L (IQR=102.3); p<0.001). Negative MR-pro-ANP and hs-cTnI at admission ruled out NSTEMI in 150/343 (43.7%) pats. with NPV of 99.3% (95.8-99.9; 95% CI).There were 9 NSTEMI pats. with negative baseline hs-cTnI (false negative) and 8/9 (88.9%) of these pats. were recognized with positive MR-proANP (>86.1 pmol/L). By employing the ‘dual biomarker’ concept, MR-pro-ANP increased the NPV of hs-cTnI for NSTEMI from 96.5% (93.7-98.4; 95% CI) to 99.3% (95.8-99.9). This favorable effect was also confirmed in time-related subgroups. In ‘early presenters’ group (onset of symptoms <6h; 47.1% of the overall study population) NPV increased from 94.7 (88.9-97.6) to 98.5% (90.1-99.9) and in ‘late presenters’ (outside 6h) NPV for NSTEMI increased from 98.7 (95.1-99.8) to 100% (94.1-100).
Conclusions: High sensitivity of MR-pro-ANP in pats. with ACS symptoms was reflected in its high value of NPV for NSTEMI when combined together with hs-cTnI (>99%), regardless of the time since onset of symptoms. Utilization of ‘dual biomarker strategy’ with MR-proANP could result in an early, rapid and reliable rule-out of NSTEMI. It had the potential to rule out NSTEMI in ca. 44% of pats. without serial blood draws.
- © 2013 by American Heart Association, Inc.