1
|
Purohit A, Radeke H, Azure M, Hanson K, Benetti R, Su F, Yalamanchili P, Yu M, Hayes M, Guaraldi M, Kagan M, Robinson S, Casebier D. Synthesis and Biological Evaluation of Pyridazinone Analogues as Potential Cardiac Positron Emission Tomography Tracers. J Med Chem 2008; 51:2954-70. [DOI: 10.1021/jm701443n] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ajay Purohit
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Heike Radeke
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Michael Azure
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Kelley Hanson
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Richard Benetti
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Fran Su
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Padmaja Yalamanchili
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Ming Yu
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Megan Hayes
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Mary Guaraldi
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Mikhail Kagan
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - Simon Robinson
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| | - David Casebier
- Research and Development, Bristol-Myers Squibb Medical Imaging, 331 Treble Cove Road, North Billerica, Massachusetts 01862, Boston University Medical School, 715 Albany Street, Boston, Massachusetts 02118, Lexicon Pharmaceuticals Inc., 350 Carter Road, Princeton, New York 08540
| |
Collapse
|
3
|
Crnac J, Schmidt MC, Theissen P, Sechtem U. Assessment of myocardial perfusion by magnetic resonance imaging. Herz 1997; 22:16-28. [PMID: 9088937 DOI: 10.1007/bf03044567] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Magnetic resonance imaging (MRI) has proven useful for anatomic and functional evaluation of the heart. However, until recently assessment of myocardial perfusion has not been possible by MRI. Using newly developed ultrafast imaging sequences, images can be acquired rapidly with a high temporal resolution, which is a prerequisite for imaging the initial passage of a bolus of MR-contrast medium through the myocardium. Only gadolinium chelates, which rapidly diffuse out of vascular space, are currently approved for clinical use. The first pass of a bolus of one of these agents through hypoperfused myocardium distal to a coronary artery stenosis enhances this area less as compared to normally perfused areas. This different myocardial enhancement is often visible when looking at the series of MR images. However, intensity differences are rapidly decreasing as MR-contrast media are diluted in the systemio circulation after the first pass and diffuse to the interstitium. Therefore, only the first pass is of interest for MR-perfusion imaging. Additional and often more precise information can be derived by measuring parameters of the signal intensity time curve such as mean transit time, maximum signal intensity increase, upslope, downslope, and delay before reaching maximum signal intensity. Temporal resolution is the crucial factor in MR-perfusion imaging because it takes only 20 to 60 seconds for the contrast medium to pass through the myocardium. Therefore, this dynamic process must be imaged with a high temporal resolution. Moreover, image acquisition must be fast enough to minimize motion artefacts and to maximize the spatial coverage of the ventricle. Ultrafast gradient echo techniques and echo planar imaging are in principle capable to fulfill these demands. While ultrafast gradient echo sequences enable one to acquire a maximum of 2 slices per heartbeat, echo planar sequences need only 30 to 50 msec to completely acquire one image and are thus able to image the entire ventricle within one heartbeat. However, they are also more susceptible to image artefacts. As gradients capable of producing high quality echo planar images are not widely available, ultrafast gradient echo techniques are commonly used for MR-perfusion imaging. A good correlation between quantitative estimates of myocardial perfusion by MRI after injection of an intravascular contrast agent and microsphere measurements has been shown in animal experiments but quantitative MR perfusion measurements have not yet been performed in humans. Clinical studies have until now focused on visual and parametric analysis of signal intensity time curves. From these studies, sensitivities and specifities in the range of 60 to 90% as compared to x-ray coronary angiography and scintigraphy were reported despite the fact that only parts of the left ventricular myocardium could be assessed. However, a generally accepted method of acquiring and analysing MR perfusion images does not yet exist. Therefore, future improvements of hardware and pulse-sequences as well as the development of new blood pool contrast agents are necessary before MR-perfusion imaging will become a widely accepted and clinically useful diagnostic procedure.
Collapse
Affiliation(s)
- J Crnac
- Klinik III für Innere Medizin, Universität zu Köln
| | | | | | | |
Collapse
|