Diagnostic value of cardiac magnetic resonance functional parameters to predict the presence of microvascular damage in the setting of reperfusion injury in STEMI

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Microvascular damage is a poor prognostic factor after STEMI and is a goal to improve its diagnosis and treatment. The aim of this work is to analyze the value of cardiac magnetic resonance (CMR) functional parameters to predict the presence of microvascular damage in the setting of reperfusion injury. Methods A cohort of patients with acute STEMI was prospectively included and systolic and diastolic blood pressure at catheterization laboratory during reperfusion procedures were assessed . All patients underwent cardiac MRI during the first week post reperfusion with a standardized protocol including functional evaluation with b-SSFP sequences and also 8-10 short axis slices in IR-FGRE sequences assessing the area of necrosis as area of signal hyper intensity> 5 Sds relative to the remote myocardium and microvascular obstruction (MVO) as signal hypointensity in the infarct core . Functional derived parameters as left ventricle (LV) and right ventricle (RV) volumes, mass and ejection fraction (LVEF, RVE ) , biventricular stroke volumes (SV), systolic and diastolic relative LV parietal mass ) and end systolic and diastolic pressure /volume (P/V) ratio were calculated and assessed in this clinical setting. Results 94 patients with reperfused STEMI were included. Forty nine of them (51%) have microvascular obstruction detected by CMR. Univariate analysis was performed showing that presence of MVO was significantly related to LV and RV ejection fraction, LVSV, end systolic biventricular volumes , systolic P / V ratio and systolic relative parietal mass. Area under ROC curve and statistic significance of analyzed data was shown in the picture. A multivariate regression model adjusted by LV ejection fraction was performed showing that LVSV (CI: 0.6-0.8 p=0.02) and systolic P / V ratio (p=0.01 CI: 0.8-0.9) as the most powerful functional predictors improving diagnostic accuracy of MVO in this clinical setting. Conclusions In addition to LV ejection fraction, LV stroke volume and systolic P / V ratio were the most powerful functional predictors associated to presence of microvascular damage in the setting of reperfused STEMI.