Acute myocardial infarction is characterized by.heterogeneous tissue injury affecting many aspects of myocardial function. Positron emission tomography (PET) in combination with tracers labeled with short-lived radionuclides allows the in-vivo assessment of specific physiologic and biochemical processes. Such physiologic imaging provide unique tissue characterization in patients with acute myocardial infarction. The extent of ischemic injury can be more accurately assessed than possible with any other non-invasive technique currently available. This proposal will focus on the on the quantitative determination of regional my cardial blood flow, the metabolic differentiation of reversible and irreversible tissue injury and the evaluation of regional catecholamine uptake by adrenergic nerve terminals in patients vith acute myocardial infarction. A new PET approach employing the flow tracer N-13 aumnia in combination with a 3-compartmental tracer kinetic model wi be validated in normal and reperfused canine myocardium using microopheres blood fl. measurements as a gold standard. Metabolic imaging with F-18 deoxyglucose and C-11 ac tate will be used to quantitatively assess oxidative and non-oxidative substrate met bolism by dynamic PET imaging and tracer kineti principles. Animal studies will a dress the value of C-11 acetate kinetics as marker of TCA cycle flux to define tiss viability. Clinically, the metabolic recovery of reperfused human myocardium will characterized and th diagnostic accuracy of the combined evaluation of flow reser and glucose utilization for definition of myor-ardium at risk and extent of necros determined. Finally, the new catecholamine analog C-11 hydroxyephedrine, which traces specifically norepinephrine uptake and storage in adrenergic nerve terminals, will used to relate regional, neuronal function to regiona blood flow and metabolism experimental and clinical myocardial infarction. Correlation of regional neuronal function with the results of electrophysiologic studies will define the potential roll of """"""""neuronal imaging"""""""" to identify high risk patients for fatal arrhythmias. The proposed research will provide new insights into substrate metabolism and neuronal function, which is expected to result in new imaging approache for the early assessment of tissue damage, risk stratification and optimization of therapeutic strategies in patients with acute infarction.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL041047-02
Application #
3358506
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1989-08-01
Project End
1994-07-31
Budget Start
1990-08-01
Budget End
1991-07-31
Support Year
2
Fiscal Year
1990
Total Cost
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Type
Schools of Medicine
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Muzik, O; Duvernoy, C; Beanlands, R S et al. (1998) Assessment of diagnostic performance of quantitative flow measurements in normal subjects and patients with angiographically documented coronary artery disease by means of nitrogen-13 ammonia and positron emission tomography. J Am Coll Cardiol 31:534-40
Brosius 3rd, F C; Liu, Y; Nguyen, N et al. (1997) Persistent myocardial ischemia increases GLUT1 glucose transporter expression in both ischemic and non-ischemic heart regions. J Mol Cell Cardiol 29:1675-85
vom Dahl, J; Muzik, O; Wolfe Jr, E R et al. (1996) Myocardial rubidium-82 tissue kinetics assessed by dynamic positron emission tomography as a marker of myocardial cell membrane integrity and viability. Circulation 93:238-45
Ficaro, E P; Fessler, J A; Shreve, P D et al. (1996) Simultaneous transmission/emission myocardial perfusion tomography. Diagnostic accuracy of attenuation-corrected 99mTc-sestamibi single-photon emission computed tomography. Circulation 93:463-73
Sawada, S; Muzik, O; Beanlands, R S et al. (1995) Interobserver and interstudy variability of myocardial blood flow and flow-reserve measurements with nitrogen 13 ammonia-labeled positron emission tomography. J Nucl Cardiol 2:413-22
Bach, D S; Beanlands, R S; Schwaiger, M et al. (1995) Heterogeneity of ventricular function and myocardial oxidative metabolism in nonischemic dilated cardiomyopathy. J Am Coll Cardiol 25:1258-62
Ficaro, E P; Fessler, J A; Ackermann, R J et al. (1995) Simultaneous transmission-emission thallium-201 cardiac SPECT: effect of attenuation correction on myocardial tracer distribution. J Nucl Med 36:921-31
Schwaiger, M; Hutchins, G (1995) Quantification of regional myocardial perfusion by PET: rationale and first clinical results. Eur Heart J 16 Suppl J:84-91
Beanlands, R S; Muzik, O; Melon, P et al. (1995) Noninvasive quantification of regional myocardial flow reserve in patients with coronary atherosclerosis using nitrogen-13 ammonia positron emission tomography. Determination of extent of altered vascular reactivity. J Am Coll Cardiol 26:1465-75
Duvernoy, C S; vom Dahl, J; Laubenbacher, C et al. (1995) The role of nitrogen 13 ammonia positron emission tomography in predicting functional outcome after coronary revascularization. J Nucl Cardiol 2:499-506

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