Abstract 1193: Unrecognized Myocardial Scars Detected by Delayed-enhanced Magnetic Resonance Imaging are Associated with Increased Levels Of N-terminal Pro-brain Natriuretic Peptide
Introduction: The levels of the cardiac biomarker, N-terminal pro-brain natriuretic peptide (NT-proBNP), are correlated to the left ventricular function. In chronic heart failure, as well as in acute myocardial infarction, higher concentrations of NT-proBNP are associated with increased cardiovascular and all-cause mortality. Hypothesis: Based on the previous knowledge that subjects with unrecognized myocardial infarction (UMI) scars detected by delayed-enhanced magnetic resonance imaging (DE-MRI) have decreased left ventricular ejection fraction, the aim of this study was to assess if that finding was reflected in the plasma levels of NT-proBNP.
Methods: Data from the Prospective Investigation of the Vasculature in Uppsala Seniors study was used. The participants who had undergone cardiac MRI were included in this study (n=248). Subjects were divided into 3 groups according to the existence of a myocardial infarction scar in DE-MRI and their hospital medical records. UMI group represented subjects with a myocardial infarction scar in DE-MRI and with no previous history of myocardial infarction. Recognized myocardial infarction (RMI) group comprised subjects with a myocardial infarction scar and with a clinical background of myocardial infarction. Subject with no myocardial scar in DE-MRI constituted the no-myocardial infarction (no-MI) group. In all subjects a peripheral blood sample was collected and the plasma levels of NT-proBNP was determined.
Results: Subjects with a UMI scar had higher plasma levels of NT-proBNP (194.46 ± 265.18 ng/L; mean±SD) than subjects in the no-MI group (126.04 ± 133.38 ng/L) (p=0.0114) and lower levels than the ones in the RMI group (310.39 ± 214.45 ng/L) (p=0.0236). The difference in NT-proBNP values between the UMI and no-MI group, remained significant after splitting the results by gender (female group, p=0.0033; male group, p=0.0384).
Conclusion: Subjects with UMI scars detected by DE-MRI have increased plasma levels of NT-proBNP, supporting the hypothesis that UMI scars might carry an increased risk of future cardiovascular adverse events.