High-resolution versus standard-resolution cardiovascular magnetic resonance perfusion imaging for the detection of coronary artery disease

Abstract

Summary This study compared the diagnostic accuracy of highresolution and standard-resolution cardiovascular magnetic resonance (CMR) perfusion imaging in patients with suspected coronary artery disease (CAD). Background Although accelerated high-spatial-resolution CMR perfusion imaging has recently been shown to be clinically feasible, there has not yet been a direct comparison with standard-resolution methods. We hypothesised that higher spatial resolution detects more subendocardial ischemia and leads to greater diagnostic accuracy for the detection of angiographically defined CAD. Methods A total of 111 patients with suspected CAD were prospectively recruited. All patients underwent two separate perfusion CMR studies on a 1.5 Tesla CMR scanner (Intera CV, Philips Healthcare, Best, the Netherlands), one with standard-resolution (2.5 x 2.5mm in-plane resolution) and one with high-resolution (1.6 x 1.6mm in-plane resolution) acquisition. High-resolution acquisition was facilitated by eight-fold k-t broad linear speed up technique (BLAST) acceleration. Two observers visually graded perfusion in each myocardial segment on a 4-point scale. Segmental scores were summed to produce a perfusion score for each patient. All patients underwent invasive coronary angiography. Significant CAD was defined as a coronary artery stenosis of ≥ 50% diameter on quantitative coronary angiography. Results CMR data were successfully obtained in 100 patients. A typical example is shown in Figure 1. In patients with CAD (n=70), more segments were determined to have subendocardial ischemia with high-resolution acquisition than with standard-resolution acquisition (279 vs.108; p<0.001). High-resolution acquisition had a greater diagnostic accuracy than standard-resolution acquisition for identifying single-vessel disease (area under the curve [AUC]: 0.88 vs. 0.73; p<0.001) or multi-vessel disease (AUC: 0.98 vs. 0.91; p=0.002) and overall (AUC: 0.93 vs. 0.83; p<0.001) (Figure 2). Conclusions Our study shows that high-resolution CMR perfusion imaging has greater diagnostic accuracy than standardresolution acquisition for the detection of CAD in both single and multi-vessel disease and detects more subendocardial ischemia. Funding