title: 13N-Ammonia PET/CT Detection of Myocardial Perfusion Abnormalities in Beagle Dogs After Local Heart Irradiation.
abstract: Our objective was to determine the potential value of13N-ammonia PET/CT myocardial perfusion imaging (MPI) for early detection of myocardial perfusion changes induced by radiation damage.Methods:Thirty-six Beagle dogs were randomly divided into a control group (n= 18) or an irradiation group (n= 18). The latter underwent local irradiation to the left ventricular anterior cardiac wall with a single dose of 20 Gy, whereas the former received sham irradiation. All dogs underwent13N-ammonia PET/CT MPI 1 wk before irradiation and at 3, 6, and 12 mo after sham or local irradiation. One week after undergoing13N-ammonia PET/CT MPI, the irradiation group underwent coronary angiography. Six randomly selected dogs from each group were sacrificed and used to detect pathologic cardiac injury at 3, 6, and 12 mo after irradiation.Results:Compared with the control group and baseline, the irradiation group showed significantly increased perfusion in the irradiated area of the heart at 3 mo after irradiation, perfusion reduction at 6 mo after irradiation, and a perfusion defect at 12 mo after irradiation. There was no significant difference in the left ventricular ejection fraction between the control and irradiation groups at baseline or at 3 mo after irradiation. The irradiation group showed a reduction of left ventricular ejection fraction compared with the control group at 6 mo (50.0% ± 8.1% vs. 59.3% ± 4.1%,P= 0.016) and 12 mo (47.2% ± 6.7% vs. 57.4% ± 3.3%,P =0.002) after irradiation. No coronary stenosis was observed in the irradiation group. Regional wall motion abnormalities appeared in the irradiated area at 6 mo after irradiation, and its extent was enlarged at 12 mo after irradiation. Pathologic changes were observed; radiation-induced myocardial tissue damage and microvascular fibrosis in the irradiated area progressively increased over time.Conclusion:13N-ammonia PET/CT MPI can dynamically detect myocardial perfusion changes together with global and regional left ventricular dysfunction induced by irradiation and may be a valuable method for monitoring radiation-induced heart disease.
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.|Department of Radiotherapy, Shanxi Academy of Medical Sciences, Affiliated Shanxi Dayi Hospital of Shanxi Medical University, Shanxi, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.|Nursing College, Shanxi Medical University, Shanxi, China; and.
authors.forename: Rui
authors.initials: R
authors.lastname: Yan
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Department of Radiological and Environmental Medicine, China Institute for Radiation Protection, Shanxi, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.
authors.forename: Min
authors.initials: M
authors.lastname: Yan
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.
authors.forename: Xinzhong
authors.initials: X
authors.lastname: Hao
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Shanxi, China lisj_nm1@sohu.com.
authors.forename: Sijin
authors.initials: S
authors.lastname: Li
mesh_terms: D000641:Ammonia; D000818:Animals; D017023:Coronary Angiography; D003326:Coronary Circulation; D004285:Dogs; D006321:Heart / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008297:Male; D055414:Myocardial Perfusion Imaging; D009590:Nitrogen Radioisotopes; D000072078:Positron Emission Tomography Computed Tomography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging
chemical_list: D009590:Nitrogen Radioisotopes; D000641:Ammonia
keywords: 13N-ammonia PET/CT; myocardial perfusion imaging; radiation-induced heart disease; radiotherapy