Quantitative low-dose rest and stress CT myocardial perfusion imaging with a whole-heart coverage scanner improves functional assessment of coronary artery disease

Abstract

ObjectiveWe evaluated the diagnostic accuracy of myocardial blood flow (MBF) and perfusion reserve (MPR) measured from low-dose dynamic contrast-enhanced (DCE) imaging with a whole-heart coverage CT scanner for detecting functionally significant coronary artery disease (CAD).MethodsTwenty one patients with suspected or known CAD had rest and dipyridamole stress MBF measurements with CT and SPECT myocardial perfusion imaging (MPI), and lumen narrowing assessment with coronary angiography (catheter and/or CT based) within 6 weeks. SPECT MBF measurements and coronary angiography were used together as reference to determine the functional significance of coronary artery stenosis. In each CT MPI study, DCE images of the whole heart were acquired with breath-hold using a low-dose acquisition protocol to generate MBF maps. Binomial logistic regression analysis was used to determine the diagnostic accuracy of CT-measured MBF and MPR (ratio of stress to rest MBF) for assessing functionally significant coronary stenosis.ResultsMean stress MBF and MPR in ischemic segments were lower than those in non-ischemic segments (1.37 ± 0.34 vs. 2.14 ± 0.64 ml/min/g; 1.56 ± 0.41 vs. 2.53 ± 0.70; p < 0.05 for all). The receiver operating characteristic curve analysis revealed that MPR (AUC 0.916, 95%CI: 0.885–0.947) had a superior power than stress MBF (AUC 0.869, 95%CI: 0.830–0.909) for differentiating non-ischemic and ischemic myocardial segments (p = 0.045). On a per-vessel and per-segment analysis, concomitant use of MPR and stress MBF thresholds further improved the diagnostic accuracy compared to MPR or stress MBF alone for detecting obstructive coronary lesions (per-vessel: 93.4% vs. 83.6% and 88.5%, respectively; per-segment: 90.0% vs. 83.7% and 83.1%, respectively). The estimated effective dose of a rest and stress CT MPI study was 3.04 and 3.19 mSv respectively.ConclusionQuantitative rest and stress myocardial perfusion measurement with a large-coverage CT scanner improves the diagnostic accuracy for detecting functionally significant coronary stenosis.

Multimodality Imaging Assessment of the Heart Before and After Stage III Non-small Cell Lung Cancer Radiation Therapy

“…Patient 1 CT MPR<2, particularly in the LAD supplied apical segments at both timepoints, were consistent with the impaired hyperemic response documented in the literature as indicative of a functionally significant luminal narrowing≥50% on CT angiography. [21] Patient 2 baseline MPR values were consistent with no hemodynamically significant attenuation of hyperemia as reported by Huang et al [7] Different responses were observed in MPR in Patient 1 when compared to Patient 2 who did not have CAD. A global reduction of MPR, with the range of (1.37-1.8) at follow-up as measured for Patient 2 could now be considered to be indicative of an impaired hyperemic response [7].…”

“…[21] Patient 2 baseline MPR values were consistent with no hemodynamically significant attenuation of hyperemia as reported by Huang et al [7] Different responses were observed in MPR in Patient 1 when compared to Patient 2 who did not have CAD. A global reduction of MPR, with the range of (1.37-1.8) at follow-up as measured for Patient 2 could now be considered to be indicative of an impaired hyperemic response [7].…”

“…A global reduction of MPR, with the range of 1.37 to 1.8 at follow-up as measured for patient 2, could now be considered to be indicative of an impaired hyperemic response. 7 …”

“… 6 Huang et al previously reported mean CT myocardial perfusion reserve (MPR) values in nonischemic (2.53 ± 0.7) and ischemic segments (1.56 ± 0.41). 7 The capability of functional MRI to acquire cine images of wall motion throughout the cardiac cycle during short breath holds of 10 to 20 seconds has developed as the gold standard for the quantitation of left ventricular ejection fraction (LVEF), end-systolic, end-diastolic, and stroke volumes (SV). 8 Marceira et al established reference ranges for healthy men (normal 95% confidence interval of LVEF: 58%-75%; left ventricle end-systolic volume [LVESV]: 30-75 mL; left ventricle end-diastolic volume [LVEDV]: 115-198 mL; and LVSV: 76-132 mL).…”

An AI Approach for Reducing Residual Motion and Noise from Myocardial Perfusion for Assessment of Coronary Artery Disease

“…Myocardial Perfusion Reserve (MPR) is the ratio of global myocardial blood flow at stress vs. rest. It is the theoretical gold standard technique for assessing myocardial ischemia in CAD [2]. Although myocardial perfusion can successfully detect and score the CAD, it often deals with some underlying problems due to the technology's nature, such as noise and residual motion.…”