%0 Journal Article
%@ 1941-9651
%A Tsaftaris, Sotirios A.
%A Zhou, Xiangzhi 
%A Tang, Richard
%A Li, Debiao
%A Dharmakumar, Rohan
%D 2012
%F eprints:1508
%I American Heart Association
%J Circulation: Cardiovascular Imaging
%K acute coronary syndrome; coronary artery disease; ischemia; BOLD; MRI
%T Detecting Myocardial Ischemia at Rest with Cardiac Phase-Resolved BOLD CMR
%U http://eprints.imtlucca.it/1508/
%X Background—Fast, noninvasive identification of ischemic territories at rest (prior to tissue-specific changes) and assessment of functional status can be valuable in the management of severe coronary artery disease. This study investigated the utility of cardiac phase-resolved Blood-Oxygen-Level-Dependent (CP-BOLD) CMR in detecting myocardial ischemia at rest secondary to severe coronary artery stenosis.    Methods and Results—CP-BOLD, standard-cine, and T2-weighted images were acquired in canines (n=11) at baseline and within 20 minutes of ischemia induction (severe LAD stenosis) at rest. Following 3-hours of ischemia, LAD stenosis was removed and T2-weighted and late-gadolinium-enhancement (LGE) images were acquired. From standard-cine and CP-BOLD images, End-Systolic (ES) and End-Diastolic (ED) myocardium were segmented. Affected and remote sections of the myocardium were identified from post-reperfusion LGE images. S/D, quotient of mean ES and ED signal intensities (on CP-BOLD and standard-cine), was computed for affected and remote segments at baseline and ischemia. Ejection fraction (EF) and segmental wall-thickening (sWT) were derived from CP-BOLD images at baseline and ischemia. On CP-BOLD images: S/D was greater than 1 (remote and affected territories) at baseline; S/D was diminished only in affected territories during ischemia and the findings were statistically significant (ANOVA, post-hoc p<0.01). The dependence of S/D on ischemia was not observed in standard-cine images. Computer simulations confirmed the experimental findings. ROC analysis showed that S/D identifies affected regions with similar performance (AUC:0.87) as EF (AUC:0.89) and sWT (AUC:0.75).    Conclusions—Preclinical studies and computer simulations showed that CP-BOLD CMR could be useful in detecting myocardial ischemia at rest. Patient studies are needed for clinical translation. 
%Z Published online before print December 18, 2012.