Stress myocardial blood flow quantified using the aortic root as the arterial input sampling location had the highest diagnostic accuracy (AUC 0.90) for detecting abnormal myocardial perfusion, performing significantly better than the clinical reference basal left ventricle (AUC 0.81, p<0.001).
Cross-Sectional (n=25)
Single-blind
No
Does arterial input function sampling at the aortic root improve the diagnostic accuracy of CMR stress myocardial perfusion quantification compared to other locations in patients with suspected or known CAD?
Aortic root-based arterial input function sampling significantly improves the diagnostic accuracy of stress myocardial blood flow estimates by CMR perfusion compared to the current clinical reference.
Absolute Event Rate: 0.9% vs 0.81%
p-value: p=<0.001
BACKGROUND: Quantification of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) by cardiovascular magnetic resonance (CMR) perfusion requires sampling of the arterial input function (AIF). While variation in the AIF sampling location is known to impact quantification by CMR and positron emission tomography (PET) perfusion, there is no evidence to support the use of a specific location based on their diagnostic accuracy in the detection of coronary artery disease (CAD). This study aimed to evaluate the accuracy of stress MBF and MPR for different AIF sampling locations for the detection of abnormal myocardial perfusion with expert visual assessment as the reference. METHODS: Twenty-five patients with suspected or known CAD underwent vasodilator stress-rest perfusion with a dual-sequence technique at 3T. A low-resolution slice was acquired in 3-chamber view to allow AIF sampling at five different locations: left atrium (LA), basal left ventricle (bLV), mid left ventricle (mLV), apical left ventricle (aLV) and aortic root (AoR). MBF and MPR were estimated at the segmental level using Fermi function-constrained deconvolution. Segments were scored as having normal or abnormal perfusion by visual assessment and the diagnostic accuracy of stress MBF and MPR for each location was evaluated using receiver operating characteristic curve analysis. RESULTS: In both normal (300 out of 400, 75 %) and abnormal segments, rest MBF, stress MBF and MPR were significantly different across AIF sampling locations (p < 0.001). Stress MBF for the AoR (normal: 2.42 (2.15-2.84) mL/g/min; abnormal: 1.71 (1.28-1.98) mL/g/min) had the highest diagnostic accuracy (sensitivity 80 %, specificity 85 %, area under the curve 0.90; p < 0.001 versus stress MBF for all other locations including bLV: normal: 2.78 (2.39-3.14) mL/g/min; abnormal: 2.22 (1.83-2.48) mL/g/min; sensitivity 91 %, specificity 63 %, area under the curve 0.81) and performed better than MPR for the LV locations (p < 0.01). MPR for the AoR (normal: 2.43 (1.95-3.14); abnormal: 1.58 (1.34-1.90)) was not superior to MPR for the bLV (normal: 2.59 (2.04-3.20); abnormal: 1.69 (1.36-2.14); p = 0.717). CONCLUSIONS: The AIF sampling location has a significant impact on MBF and MPR estimates by CMR perfusion, with AoR-based stress MBF comparing favorably to that for the current clinical reference bLV.
Milidonis et al. (Mon,) conducted a cross-sectional in Coronary artery disease (n=25). Aortic root (AoR) arterial input sampling vs. Basal left ventricle (bLV) sampling was evaluated on Diagnostic accuracy (Area Under the Curve) of stress myocardial blood flow for detecting abnormal myocardial perfusion (95% CI 0.87-0.93, p=<0.001). Stress myocardial blood flow quantified using the aortic root as the arterial input sampling location had the highest diagnostic accuracy (AUC 0.90) for detecting abnormal myocardial perfusion, performing significantly better than the clinical reference basal left ventricle (AUC 0.81, p<0.001).