当前位置： SCI文献检索 > ANNALS OF NUCLEAR MEDICINE期刊下所有文献 > Assessment of absolute Tc-99m tetrofosmin retention in the myocardium as an index of myocardial blood flow and coronary flow reserve by gated-SPECT/CT: a feasibility study.

Assessment of absolute Tc-99m tetrofosmin retention in the myocardium as an index of myocardial blood flow and coronary flow reserve by gated-SPECT/CT: a feasibility study.

Abstract：

OBJECTIVE:Estimation of myocardial blood flow (MBF) and coronary flow reserve (CFR) by SPECT myocardial perfusion imaging (MPI) remains challenging. Our aim was to approximate MBF and CFR by quantifying the absolute Tc-99m tetrofosmin retention in the myocardium via gated-SPECT/CT MPI. METHODS:Tracer retention was calculated on the basis of the microsphere kinetic model and served as an index of MBF at stress and rest (sMBFi, rMBFi). CFR was given by the sMBFi/rMBFi ratio. A planar first-pass acquisition during dipyridamole stress and at rest provided the data for tracer input determination. The input was represented by the integral of a gamma variate fitted on the time-activity curve of the left ventricle. Gated-SPECT/CT was performed 1 h post tracer injection and myocardial activity was measured in attenuation-corrected transaxial slices by a threshold VOI. The input was also compensated for tissue attenuation by measuring the distance from the centre of the left ventricle to the body surface on fused SPECT/CT slices. Input and uptake results were adjusted for planar-SPECT counting geometry differences by the aid of a phantom experiment. Thirty-nine subjects with low probability of coronary artery disease (CAD), age lower than 75 years and normal MPI (control group) were compared with 57 patients with documented CAD (CAD group). RESULTS:CFR and sMBFi values of CAD patients (1.39 ± 0.37 and 1.42 ± 0.35 ml/min/g) were considerably lower (p < 0.0001) than controls (1.68 ± 0.25 and 1.72 ± 0.37 ml/min/g). Significant difference in CFR (p = 0.03) was also noted between CAD patients with normal MPI (1.48 ± 0.38) and controls. However, sMBFi managed to discriminate certain CAD subgroups (normal MPI/ischemia/scar/scar and ischemia) more efficiently than CFR. Maximum heart rate-blood pressure product (RPP) during stress was an independent predictor of sMBFi and CFR. The other independent CFR correlates were resting RPP and diabetes mellitus, while sMBFi was associated with age, sex, smoking, and stress perfusion defects. CONCLUSIONS:Despite the low myocardial extraction fraction of Tc-99m tetrofosmin, an approximation of MBF and CFR is feasible with gated-SPECT/CT MPI. These flow indices together were able to discriminate CAD patients from controls and stratify different patient subgroups.

journal_name

Ann Nucl Med

journal_title

Annals of nuclear medicine

authors

Apostolopoulos DJ,Kaspiri A,Spyridonidis T,Patsouras N,Savvopoulos CA,Davlouros P,Vassilakos PJ,Alexopoulos D

doi

10.1007/s12149-015-0982-6

subject

Has Abstract

pub_date

2015-08-01 00:00:00

pages

588-602

issue

eissn

0914-7187

issn

1864-6433

journal_volume

pub_type

临床试验,杂志文章

在线工具

Assessment of absolute Tc-99m tetrofosmin retention in the myocardium as an index of myocardial blood flow and coronary flow reserve by gated-SPECT/CT: a feasibility study.