Abstract 10654: Absolute Hyperemic Myocardial Blood Flow is Impaired in Non-Ischemic Dilated Cardiomyopathy and is Related to the Severity of Left Ventricular Systolic Dysfunction

Introduction: Myocardial perfusion reserve (MPR) is reduced in non-ischemic DCM. Microvascular ischemia may therefore be important in this condition. Since MPR is a ratio, absolute hyperemic myocardial blood flow (MBF) is a superior index of maximal perfusion. CMR perfusion imaging allows quantification of hyperemic MBF with high spatial resolution. We hypothesized that impaired hyperemic MBF can be detected in DCM by CMR and is related to the degree of LV systolic dysfunction (LVSD). Methods: Consecutive DCM patients referred for CMR and age/sex matched healthy controls were prospectively enrolled. Exclusion criteria included IHD, diabetes and severe hypertension. Patients were classified as having severe LVSD or mild/moderate LVSD based on an LVEF cut-off of 35%. CMR first-pass perfusion imaging (1.5T) was performed during adenosine-induced hyperemia and at rest. Hyperemic and rest global MBF were quantified by Fermi function deconvolution. Results: In total 67 patients (50 male, mean age 52 yrs, mean L...