Towards whole-heart quantitative myocardial perfusion using a dual-sequence framework with multiband acceleration
Background2D Quantitative Myocardial Perfusion (Qperf) MRI is limited by its inability to provide complete myocardial coverage within a heartbeat interval. This study developed and evaluated dual saturation multiband-accelerated Qperf imaging to achieve near-complete left ventricular coverage in free-breathing at an adequate in-plane spatial resolution, using a semi-automated Myocardial Blood Flow (MBF) framework for quantification deployable directly on the scanner console. MethodsA dual-saturation single-band QPerf sequence was modified for multiband imaging, enabling the acquisition of 6 high-resolution myocardial slices plus Arterial Input Function (AIF) during free-breathing. The technique was evaluated in 16 sedated pigs (13 healthy and 3 with LAD occlusion) under rest conditions on a 3T MRI scanner. Additionally, two healthy pigs underwent stress imaging as well. Statistical comparisons were performed between multiband and single-band MBF values in corresponding AHA segments. ResultsQualitatively, multiband QPerf provided superior left ventricular coverage and comparable image quality to single-band Qperf MBF maps, potentially enabling a more comprehensive detection of perfusion defects at rest. Quantitatively, multiband QPerf yielded lower MBF values than single-band QPerf (p < 0.01). However, Bland-Altman analysis (mean difference: -0.17 ml/min/g; 95% CI: -1.12 to 0.79 ml/min/g) and Passing-Bablok regression (intercept: -0.01 ml/min/g; 95% CI: - 0.37 to 0.28 ml/min/g) indicated that such discrepancy remained within the expected confidence intervals. Furthermore, the Passing-Bablok slope (0.88; 95% CI: 0.73-1.06) confirmed that mb-QPerf maintained sensitivity comparable to sb-QPerf in detecting perfusion changes under rest conditions. Finally, there was an overall increase in MBF values during stress vs rest conditions (average MBF Ratio 1.67 {+/-} 0.31) when comparing healthy pigs. ConclusionMultiband-accelerated Qperf is feasible, providing improved left ventricular coverage, adequate in-plane resolution, and a semi-automated MBF quantification framework directly on the scanner console. Compared to its single-band counterpart, multiband QPerf demonstrated a more comprehensive visualization of perfusion defects and comparable sensitivity and accuracy in detecting perfusion changes at rest. Further research and clinical validation in patient populations are needed to confirm its utility in the diagnosis of coronary artery disease.