scholarly journals Single- or dual-bolus approach for the assessment of myocardial perfusion reserve in quantitative MR perfusion imaging

2008 ◽  
Vol 59 (6) ◽  
pp. 1373-1377 ◽  
Author(s):  
Wolfgang Utz ◽  
Andreas Greiser ◽  
Thoralf Niendorf ◽  
Rainer Dietz ◽  
Jeanette Schulz-Menger
Keyword(s):  
Myocardial Perfusion ◽  
Perfusion Imaging ◽  
Myocardial Perfusion Reserve ◽  
Mr Perfusion ◽  
Perfusion Reserve ◽  
Mr Perfusion Imaging ◽  
Quantitative Mr ◽  
Dual Bolus

scholarly journals Molecular Mechanisms of Adenosine Stress T1 Mapping

2021 ◽  
Author(s):  
Soham A. Shah ◽  
Claire E. Reagan ◽  
Brent A. French ◽  
Frederick H. Epstein
Keyword(s):  
Magnetic Resonance Imaging ◽  
Heart Rate ◽  
Magnetic Resonance ◽  
Myocardial Perfusion ◽  
Perfusion Imaging ◽  
T1 Mapping ◽  
Myocardial Perfusion Reserve ◽  
Adenosine Stress ◽  
Resonance Imaging ◽  
Perfusion Reserve

Background: Adenosine stress T1 mapping is an emerging magnetic resonance imaging method to investigate coronary vascular function and myocardial ischemia without application of a contrast agent. Using gene-modified mice and 2 vasodilators, we elucidated and compared the mechanisms of adenosine myocardial perfusion imaging and adenosine T1 mapping. Methods: Wild-type (WT), A 2A AR −/− (adenosine A 2A receptor knockout), A 2B AR −/− (adenosine A 2B receptor knockout), A 3 AR −/− (adenosine A 3 receptor knockout), and eNOS −/− (endothelial nitric oxide synthase knockout) mice underwent rest and stress perfusion magnetic resonance imaging (n=8) and T1 mapping (n=10) using either adenosine, regadenoson (a selective A 2A AR agonist), or saline. Myocardial blood flow and T1 were computed from perfusion imaging and T1 mapping, respectively, at rest and stress to assess myocardial perfusion reserve and T1 reactivity (ΔT1). Changes in heart rate for each stress agent were also calculated. Two-way ANOVA was used to detect differences in each parameter between the different groups of mice. Results: Myocardial perfusion reserve was significantly reduced only in A 2A AR −/− compared to WT mice using adenosine (1.06±0.16 versus 2.03±0.52, P <0.05) and regadenoson (0.98±026 versus 2.13±0.75, P <0.05). In contrast, adenosine ΔT1 was reduced compared with WT mice (3.88±1.58) in both A 2A AR −/− (1.63±1.32, P <0.05) and A 2B AR −/− (1.55±1.35, P <0.05). Furthermore, adenosine ΔT1 was halved in eNOS −/− (1.76±1.46, P <0.05) versus WT mice. Regadenoson ΔT1 was approximately half of adenosine ΔT1 in WT mice (1.97±1.50, P <0.05), and additionally, it was significantly reduced in eNOS −/− mice (−0.22±1.46, P <0.05). Lastly, changes in heart rate was 2× greater using regadenoson versus adenosine in all groups except A 2A AR −/− , where heart rate remained constant. Conclusions: The major findings are that (1) although adenosine myocardial perfusion reserve is mediated through the A 2A receptor, adenosine ΔT1 is mediated through the A 2A and A 2B receptors, (2) adenosine myocardial perfusion reserve is endothelial independent while adenosine ΔT1 is partially endothelial dependent, and (3) ΔT1 mediated through the A 2A receptor is endothelial dependent while ΔT1 mediated through the A 2B receptor is endothelial independent.

scholarly journals Assessing the reliability of DP and Fermi estimates in single and dual bolus cardiac MR perfusion imaging

2014 ◽  
Vol 16 (S1) ◽  
Author(s):  
Giorgos Papanastasiou ◽  
Michelle C Williams ◽  
Shirjel Alam ◽  
Mark Dweck ◽  
Saeed Mirsadraee ◽  
...  
Keyword(s):  
Perfusion Imaging ◽  
Mr Perfusion ◽  
Cardiac Mr ◽  
Mr Perfusion Imaging ◽  
Dual Bolus

scholarly journals Effects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot study

2010 ◽  
Vol 53 (3) ◽  
pp. 185-191 ◽  
Author(s):  
Ameneh Mashayekh ◽  
Dzung L. Pham ◽  
David M. Yousem ◽  
Mercedes Dizon ◽  
Peter B. Barker ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Pilot Study ◽  
Perfusion Imaging ◽  
Ginkgo Biloba ◽  
Mr Perfusion ◽  
Mr Perfusion Imaging ◽  
Quantitative Mr

Epicardial coronary stenosis severity and myocardial perfusion

2020 ◽  
pp. 12-16
Keyword(s):  
Myocardial Perfusion ◽  
Myocardial Ischemia ◽  
Coronary Disease ◽  
Myocardial Perfusion Reserve ◽  
Pharmacological Intervention ◽  
Fractional Flow ◽  
Perfusion Reserve ◽  
Flow Reserve ◽  
Stenosis Severity ◽  
Microvascular Resistance

Patients suspected of having epicardial coronary disease are often investigated with noninvasive myocardial ischemia tests to establish a diagnosis and guide management. However, the relationship between myocardial ischemia and coronary stenoses is affected by multiple factors, and there is marked biological variation between patients. The ischemic cascade represents the temporal sequence of pathophysiological events that occur after interruption of myocardial oxygen delivery. The earliest part of the cascade is examined via perfusion imaging, and fractional flow reserve (FFR) is a corresponding index which is specific to the coronary artery. Whereas FFR has come to be regarded a clinical reference standard against which other newer invasive and noninvasive tests are validated, the diagnostic FFR threshold for detecting ischemia was established against a combination of noninvasive ischemia tests that assessed different stages of the ischemic cascade. Moreover, the validity of invasive pressure-derived indices of stenosis severity are contingent on the assumption that pressure is proportional to flow if microvascular resistance is constant, a condition induced by pharmacological intervention or by examining specific segments of the cardiac cycle. Furthermore, myocardial perfusion reserve depends on dynamic modulation of microvascular resistance, and dysfunction of the microvasculature can lead to ischemia even in the absence of epicardial coronary disease.

MR perfusion imaging: Half‐dose gadolinium is half the quality

2021 ◽  
Author(s):  
Jeremy J. Heit ◽  
Soren Christensen ◽  
Michael Mlynash ◽  
Michael P. Marks ◽  
Tobias D. Faizy ◽  
...  
Keyword(s):  
Perfusion Imaging ◽  
Mr Perfusion ◽  
Mr Perfusion Imaging ◽  
Half Dose
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