PT  - JOURNAL ARTICLE
AU  - Eiji Tadamura
AU  - Marcelo Mamede
AU  - Shigeto Kubo
AU  - Hiroshi Toyoda
AU  - Masaki Yamamuro
AU  - Hidehiro Iida
AU  - Nagara Tamaki
AU  - Kazunobu Nishimura
AU  - Masashi Komeda
AU  - Junji Konishi
TI  - The Effect of Nitroglycerin on Myocardial Blood Flow in Various Segments Characterized by Rest-Redistribution Thallium SPECT
DP  - 2003 May 01
TA  - Journal of Nuclear Medicine
PG  - 745--751
VI  - 44
IP  - 5
4099  - http://jnm.snmjournals.org/content/44/5/745.short
4100  - http://jnm.snmjournals.org/content/44/5/745.full
SO  - J Nucl Med2003 May 01; 44
AB  - The use of nitrates is reported to be effective in viability detection in scintigraphic perfusion imaging. The purpose of the study was to evaluate the effect of nitroglycerin (NTG) on myocardial blood flow (MBF) and coronary vascular resistance (CVR) in various segments characterized by rest-redistribution 201Tl SPECT. Methods: Twenty-three patients with coronary artery disease underwent rest-redistribution 201Tl SPECT and 15O-labeled water PET at rest and after NTG spray (0.3 mg). In addition, 11 healthy volunteers were also studied using PET. Results: NTG did not change global MBF in the volunteers or in the patients. In segments with normal 201Tl uptake and in those with a severe irreversible 201Tl defect, NTG significantly reduced MBF without changing CVR. NTG reduced CVR in segments with a reversible 201Tl defect (141 ± 50 to 114 ± 29 mm Hg/[mL/min/g], P = 0.004) and in those with a mild-to-moderate irreversible 201Tl defect (165 ± 64 to 149 ± 60 mm Hg/[mL/min/g], P = 0.003), while maintaining MBF. Conclusion: NTG preferentially reduces CVR in the viable myocardium with ischemia. After NTG, tracer uptake in the ischemic myocardium will be relatively increased compared with that in the nonviable and nonischemic myocardium, leading to improvements in viability detection.