Quantitative Myocardial Perfusion Using Conventional Single-Bolus Contrast Imaging Overestimates Absolute Myocardial Blood Flow Compared with Dual-Bolus or Dual-Sequence Cardiac MR Methods

Introduction: Estimates of myocardial blood flow (MBF) from first-pass contrast-enhanced cardiac magnetic resonance (CMR) imaging require accurate measurement of the arterial input function (AIF) from the left-ventricular (LV) blood pool. Both dual-bolus [1] and dual-sequence [2,3] CMR methods have been proposed to maintain the linearity of the LV signal during the contrast passage. Several studies have compared quantitative estimates of CMR perfusion using single-bolus and dual-bolus contrast methods [4,5]. These studies used a hybrid echo-planar imaging (EPI) sequence and showed both single-bolus and dual-bolus methods were clinically applicable for quantitative evaluation of coronary artery disease (CAD) in patients. However, it was further shown that myocardial perfusion reserve (MPR) was comparable for both single-bolus and dual-bolus methods [5]. A balanced steady-state free precession (SSFP) sequence can theoretically achieve a higher degree of T1 linearity and SNR compared to the hybridEPI sequence [6]. This study is aimed to compare MBF estimates from single-bolus, dual-bolus, and dual-sequence CMR perfusion imaging methods using a SSFP sequence. MBF estimated from CMR perfusion images were compared to microsphere absolute MBF measurements in animals.