C-reactive protein, infarct size, microvascular obstruction, and left-ventricular remodelling following acute myocardial infarction

This study assessed the relationship between inflammatory mediators and indices of infarct size and left-ventricular (LV) remodelling following successful primary percutaneous coronary intervention (PCI) in patients with first time ST elevation myocardial infarction (MI).

Forty-two patients admitted with an occluded single vessel were recruited consecutively. Cardiac magnetic resonance was used for serial assessment (2 days, 1 week, 2 months) of infarct size, microvascular obstruction (MO), and LV remodelling. Inflammatory mediators were analysed before and after PCI. Our major findings were: (1) Following PCI, there was a marked increase in plasma levels of C-reactive protein, closely correlated with an increase in interleukin-6 and terminal complement complex, reaching maximum 2 days after PCI; (2) C-reactive protein 2 days after PCI was significantly correlated with infarct size and parameters of LV remodelling 2 months after PCI; (3) Patients with persistent MO had significantly higher C-reactive protein levels 2 days following PCI.

We suggest that the rapid increase in C-reactive protein levels in this model of successful revascularization of a single, totally occluded vessel reflects the degree of inflammation within the infarcted area. Our findings support a role for C-reactive protein-mediated complement activation as both a marker and mediator of myocardial damage following MI.

Clinical study no.: NCT 00465868.