Comparison of single to dual bolus MR myocardial perfusion imaging for detection of coronary artery disease

Introduction Absolute myocardial perfusion can be determined using first pass MR myocardial perfusion imaging with a Fermi-model constrained deconvolution [1]. In the analysis, a linear relationship between contrast concentration and signal intensity is mostly assumed. However, at high contrast concentration saturation effects cause a non linear effect. As low contrast concentrations limits the contrast to noise ratio, a dual bolus technique has recently been introduced to compensate for the saturation effect in the blood pool where the arterial input function is derived [2]. The dual bolus approach has shown to provide absolute perfusion values comparable to values determined by microspheres in animals [3] and positron emission tomography (PET) in healthy volunteers [4]. In clinical practice, MR perfusion imaging is used as a diagnostic tool in patients with suspected coronary artery disease (CAD). The main objective of this study was to investigate the incremental diagnostic value for detection of significant CAD of the dual bolus over the single contrast bolus technique. Secondly, this study compared dual bolus absolute perfusion values to values obtained from the single contrast bolus technique in patients with no or only mild CAD, as a reproduction of earlier studies.