Abstract
BackgroundQuantification 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.ResultsIn 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).ConclusionsThe 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.
Highlights
Quantification of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) by cardiovas‐ cular magnetic resonance (CMR) perfusion requires sampling of the arterial input function (AIF)
Our findings demonstrate that while stress MBF and MPR for all considered AIF sampling locations are able to distinguish between myocardium with normal and abnormal perfusion, perfusion measurements for the two groups are different depending upon the AIF location used
It is important to note that the diagnostic performance of the left ventricular (LV) locations as assessed by receiver operating characteristic (ROC)-Area under the curve (AUC) does not correlate with their anatomical location, as each may be impacted to a different extent by aforementioned factors
Summary
Quantification of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) by cardiovas‐ cular 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). Central to MBF quantification is the arterial input function (AIF) which describes the contrast agent input to the myocardium [10] It has been known since early theoretical developments of tracer-based flow measurement that accurate quantification requires the AIF to be sampled at the true myocardial input [11, 12]. Current perfusion quantification pipelines measure the AIF in the much larger basal left ventricular (LV) cavity instead, which offers the additional advantage of being imaged in the same slice as the myocardium and is usually free from myocardial trabeculation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
