Background: C-reactive protein velocity (CRPv) has been proposed as a very early and sensitive risk predictor in patients with ST-elevation myocardial infarction (STEMI). However, the association of CRPv with early left ventricular (LV) dysfunction after STEMI is unknown.

Purpose: The aim of this study was to investigate the relationship between CRPv and early LV dysfunction, before or at hospital discharge, in patients with first STEMI.

Methods: This analysis evaluated 432 STEMI patients that were included in the prospective MARINA-STEMI (Magnetic Resonance Imaging In Acute ST-elevation Myocardial Infarction. ClinicalTrials.gov Identifier: NCT04113356) cohort study. The difference of CRP 24±8h and CRP at hospital admission, divided by the time (in h) that elapsed during the two examinations, was defined as CRPv. Cardiac magnetic resonance (CMR) imaging was conducted at a median of 3 [IQR:2-4] days after primary percutaneous coronary intervention (PCI) for determination of LV function and myocardial infarct characteristics. The association of CRPv with CMR-derived LV ejection fraction (LVEF) was investigated.

Results: Median CRPv was 0.42 [IQR 0.21-0.76] mg/l/h and correlated with LVEF (r_S= -0.397, p<0.001). In multivariable linear as well as binary logistic regression analysis (adjustment for biomarkers, clinical and angiographical parameters), CRPv was independently associated with LVEF (β: 0.161, p=0.004) and LVEF≤40% (OR: 1.71, 95% CI: 1.19-2.45; p=0.004), respectively. The combined predictive value of peak cardiac troponin T (cTnT) and CRPv for LVEF≤40% (AUC: 0.81, 95% CI 0.77-0.85, p<0.001) was higher than for peak cTnT alone (AUC difference: 0.04, p=0.009).

Conclusion: CRPv was independently associated with early LV dysfunction, as measured by CMR determined LVEF, revealing an additive predictive value over cTnT after acute STEMI treated with primary PCI.