Importance of infarct size versus other variables for clinical outcomes after PPCI in STEMI patients

Despite promising experimental studies and encouraging proof-of-concept clinical trials, interventions aimed at limiting infarct size have failed to improve clinical outcomes in patients with ST-elevation myocardial infarction (STEMI). Our objective was to examine whether variables (cardiovascular risk factors, comorbidities, post-procedural variables, cotreatments) might be associated with clinical outcomes in STEMI patients independently from infarct size reduction. The present study was based on a post hoc analysis of the CIRCUS trial database (Clinicaltrials.gov NCT01502774) that assessed the clinical benefit of a single intravenous bolus of cyclosporine in 969 patients with anterior STEMI. Since cyclosporine had no detectable effect on clinical outcomes as well as on any measured variable, we here considered the whole study population as one group. Multivariate analysis was performed to address the respective weight of infarct size and variables in clinical outcomes. Multivariate analysis revealed that several variables (including gender, hypertension, renal dysfunction, TIMI flow grade post-PCI < 3, and treatment administered after PCI with betablockers and angiotensin-converting enzyme inhibitors) had per se a significant influence on the occurrence of [death or hospitalization for heart failure] at 1 year. The relative weight of infarct size and variables on the composite endpoint of [death or hospitalization for heart failure] at 1 year was 18% and 82%, respectively. Several variables contribute strongly to the clinical outcomes of STEMI patients suggesting that cardioprotective strategy might not only focus on infarct size reduction.