Magnetic resonance myocardial first‐pass perfusion imaging: Parameter optimization for signal response and cardiac coverage

Abstract

Fast imaging techniques allow monitoring of contrast medium (CM) first‐pass kinetics in a multislice mode. Employing shorter recovery times improves cardiac coverage during first‐pass conditions, but potentially flattens signal response in the myocardium. The aim of this study was therefore to compare in patients with suspected coronary artery disease (CAD) two echo‐planar imaging strategies yielding either extended cardiac coverage or optimized myocardial signal response (protocol A/B, six/four slices; preparation pulse, 60°/90°; delay time, 10/120 msec; readout flip angle, 10°/50°; respectively). In phantoms and myocardium of normal volunteers (N= 10) the CM‐induced signal increase was 2.5–3 times higher with protocol B (P < 0.005) than with protocol A. For the detection of individually diseased coronary arteries (≥1 stenosis with ≥50% diameter reduction on quantitative coronary angiography (QCA)), receiver‐operator characteristics of protocol B (signal upslope in 32 sectors/heart) yielded a sensitivity/specificity of 82%/73%, which was superior to protocol A (P < 0.05, N= 14). For the overall detection of CAD, the sensitivity/specificity of protocol B was 85%/81%. An adequate signal response in the myocardium is crucial for a reliable detection of perfusion deficits during first‐pass conditions. The presented protocol B detects CAD with a sensitivity and specificity similar to scintigraphic techniques. J. Magn. Reson. Imaging 2001;14:556–562.