Prognostic Value of Functional Variables as Assessed by Gated Thallium-201 Myocardial Perfusion Single Photon Emission Computed Tomography for Major Adverse Cardiac Events in Patients with Coronary Artery Disease.
OBJECTIVE
Gated single photon emission computed tomography (SPECT) using thallium-201 (Tl-201) has the capacity to evaluate the earlier post-stress (PS) function compared to technetium-99m labeled tracers, and may be more sensitive in detecting transient ventricular dysfunction caused by stress-induced ischemia. The purpose of this study was to assess the prognostic value of functional variables obtained from Tl-201 gated SPECT as a predictor of major adverse cardiac events (MACE).


METHODS
Four hundred and thirty-eight subjects who had known or suspected coronary artery disease and underwent clinically indicated dipyridamole-stress electrocardiography-gated Tl-201 SPECT were included in this study. Functional variables, including PS-ejection fraction (EF), PS-end systolic volume (ESV), PS-regional wall motion abnormality (RWA), reversible RWA and EF worsening, were generated to study the correlation with MACE (cardiac death, nonfatal infarction, unstable angina and coronary revascularization).


RESULTS
Sixty-eight of the total 438 patients (15.5%) had MACE during the period of follow-up (a median time of 31 months), including 2 cardiac deaths, 9 non-fatal infarctions, 9 unstable angina and 48 coronary revascularizations. These events occurred significantly more frequently in patients with reversible RWA (28.8% vs. 7.1%, p < 0.0001), EF worsening (34.8% vs. 12.1%, p < 0.0001), PS-RWA (29.9% vs. 11.4%, p < 0.0001) and PS-EF < 45% (27.8% vs. 14.4%, p = 0.034). Using the Cox proportional hazards regression analysis, reversible RWA and EF worsening were two independent predictors of MACE, providing incremental prognostic value over clinical and perfusion-alone information.


CONCLUSIONS
The functional assessment with Tl-201 gated SPECT was a useful prognosticator for patients who had known or suspected coronary artery disease.


BACKGROUND
Coronary artery disease; Gated SPECT; Major adverse cardiac events; Tl-201.
Department of Cardiology, Show Chwan Memorial Hospital;
Thau-Yun
TY
Shen
Department of Nuclear Medicine, Changhua Christian Hospital;
Ming-Che
MC
Chang
Department of Nuclear Medicine, Chang-Bing Show Chwan Memorial Hospital, Changhua; ; Department of Biomedical Imaging and Radiological Science;
Guang-Uei
GU
Hung
School of Medicine, China Medical University, Taichung, Taiwan;
Chia-Hung
CH
Kao
Nuclear Science and Engineering Institute, University of Missouri-Columbia, Columbia, Missouri, USA.
Bailing
B
Hsu