Circulating miR-1 as a potential predictor of left ventricular remodeling following acute ST-segment myocardial infarction using cardiac magnetic resonance

Background: The identification of patients with a high likelihood of left ventricular (LV) remodeling with a high-risk prognosis has critical implications for risk stratification after acute ST-segment elevation myocardial infarction (STEMI). This study aimed to evaluate the relationship between circulating miR- 1 and 6-month post-infarct LV remodeling based on cardiac magnetic resonance (CMR) imaging. Methods: A total of 80 patients with a first STEMI treated with primary percutaneous coronary intervention (PCI) who underwent CMR imaging 1 week and 6 months after STEMI were evaluated. The percentage changes of LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), LV end- systolic volume index (LVESV) at 1 week and 6 months after PCI (%Delta LVEF, %Delta LVEDV and %Delta LVESV) were calculated. miR-1 was measured using polymerase chain reaction (PCR)-based technologies in plasma samples that were collected at admission. The study group was divided into two groups based on a 10% cutoff value for the percentage of change in the LV end-diastolic volume (%Delta LVEDV): remodeling at high risk of major adverse cardiac events (MACEs) (%Delta LVEDV =10%, termed the LV remodeling group) and remodeling at lower risk of MACEs (%Delta LVEDV <10%, termed the non-LV remodeling group). The associations of miR-1 expression with the %Delta LVEDV, percentage change in the LV end-systolic volume (%Delta LVESV), and percentage change in the LV ejection fraction at follow-up were estimated. Results: Twenty-two patients (27.5%) showed adverse LV remodeling, and 58 patients (72.5%) did not show adverse LV remodeling at the 6-month follow-up of CMR. The mean LVEF, LVEDV index, and LVESV index values at 1 week were 50.6%+/- 8.2%, 74.6 +/- 12.8 mL/m(2), and 37.2 +/- 10.2 mL/m(2), respectively. Mean LVEF at follow-up (53.5%+/- 10.6%) was increased compared with baseline (P<0.001). There were significant decreases in LVEDV index and LVESV index values at follow- up (72.0 +/- 14.9 mL/m(2) and 33.7 +/- 11.0 mL/m(2), respectively; P=0.009 and P<0.001, respectively). The expression of miR-1 at admission was positively correlated with the %Delta LVEDV (r=0.611, P<0.001) and %.LVESV (r=0.268, P=0.016). Receiver operating characteristic (ROC) analysis showed that miR-1 expression predicted LV remodeling with an area under the curve (AUC) value of 0.68 (95% CI: 0.56-0.78). Compared with the clinical factors of peak creatine kinase-myocardial band (CK-MB) and peak troponin T level, peak logNT-proBNP showed the highest predictive power, with an AUC value of 0.75 (95% CI: 0.64-0.84). A model including the clinical, CMR, and miR-1 factors showed greater predictive power (P=0.034) than a model including only clinical and CMR factors, with AUCs of 0.89 (95% CI: 0.80-0.95) and 0.81 (95% CI: 0.71-0.89), respectively. Conclusions: Circulating miR-1 at admission is an independent predictor of LV remodeling 6 months after STEMI. miR-1 showed incremental value in predicting LV remodeling compared with the clinical and CMR measurements.