Tl-201 Redistribution SPECT and N-13 Ammonia PET Images in Patients with Old Myocardial Infarction and Left Ventricular Dysfunction: Segmental Comparison and Discordance Analysis.
- Author:
Joon Young CHOI
1
;
Kyung Han LEE
;
Young Hwan KIM
;
Eun Jeong LEE
;
Hyun Woo CHUNG
;
Su Jin LEE
;
Sang Hoon LEE
;
Byung Tae KIM
Author Information
1. Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. khleenm@samsung.co.kr
- Publication Type:Original Article
- Keywords:
Myocardial infarction;
Myocardial SPECT;
Myocardial PET;
Tl-201;
N-13 ammonia;
Attenuation artifact
- MeSH:
Ammonia*;
Dilatation;
Dipyridamole;
Humans;
Metabolism;
Myocardial Infarction*;
Perfusion;
Thallium;
Tomography, Emission-Computed, Single-Photon*;
Ventricular Dysfunction, Left*
- From:Korean Journal of Nuclear Medicine
2004;38(3):218-224
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
We compared rest perfusion PET with redistribution perfusion SPECT to investigate the concordant rate between PET and SPECT images and analyze the discordant pattern. MATERIALS AND METHODS: Rest N-13 ammonia and F-18 FDG PET were performed on 18 patients with old myocardial infarction and left ventricular dysfunction whose dipyridamole - 4hr redistribution Tl-201 SPECT showed one or more severe fixed defects. Regional perfusion and metabolism were evaluated visually and quantitatively with 5-segment myocardial model. RESULTS: There were high concordant rate in uptake pattern (80/90 segments, 88.9%) and high correlation coefficient on quantitative analysis (R=0.81, p< 0.001) between redistrubution Tl-201 SPECT and N-13 ammonia PET images. Nine of 18 patients had SPECT-PET concordant pattern (Group I). Ten segments (9 in inferior wall, 1 in apex) from the remaining 9 patients showed SPECT-PET discordant pattern with abnormal Tl-201 defect and near normal N-13 ammonia uptake (Group II). The diastolic and systolic left ventricular dimensions were significantly increased in Group II compared to those of Group I. When attenuation uncorrected N-13 ammonia PET images were reconstructed in Group II, it resulted in PET images with severe inferior wall defects nearly identical to those seen in redistribution Tl-201 SPECT images. CONCLUSION: Redistribution Tl-201 SPECT images showed high concordant rate and correlation with rest N-13 ammonia PET images. Most of discordant segments had fixed thallium defects in inferior wall with nearly normal N-13 ammonia uptake, which may result from severe left ventricular dilatation and attenuation by the left hemidiaphragm and cardiac blood pool.
