Abstract 9268: NT-proBNP and Myocardial Perfusion in Asymptomatic Adults: The Multi-Ethnic Study of Atherosclerosis (MESA)

Abstract

Introduction: B-type natriuretic peptide (BNP) is a cardiac neurohormone secreted from membrane granules in the cardiac ventricles as a response to ventricular volume expansion and pressure overload. While it is a sensitive marker of heart failure, it may also be elevated in the setting of reduced myocardial perfusion. We hypothesized that reduced myocardial blood flow (MBF) would be associated with elevated NT-proBNP in the MESA study. Methods: MBF was measured by cardiac MRI in 184 MESA participants without overt coronary heart disease, before and after adenosine infusion, for whom serum NT-proBNP levels were available (mean age 60 ± 10.4, 58% white, 42% Hispanic, 44% female). Hyperemic MBF was modeled with adjustment for resting MBF. A linear regression analysis, adjusted for demographics, established cardiovascular risk factors, left ventricular mass, body mass index and medications, was used to determine the association between hyperemic MBF and NT-proBNP. Results: Individuals with low hyperemic MBF were more likely to be older, male, diabetic, have higher blood pressure and higher coronary artery calcium (CAC) score. Hyperemic MBF was 3.04 ± 0.829 ml/min/g and was inversely associated with NT-proBNP levels. In the fully adjusted model, every one standard deviation decrement in hyperemic MBF was associated with a 21% increment in NT-proBNP (p=0.04) (TABLE). Conclusions: Hyperemic MBF is inversely associated with NT-proBNP level in this cross sectional study of asymptomatic individuals free of overt coronary artery disease. These results suggest that higher NT-proBNP levels may signify subclinical myocardial microvascular dysfunction.