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Aims The purpose of this study was to examine the prognostic significance of uptake patterns on quantitative myocardial 123I- m IBG and 99mTc-tetrofosmin SPECT imaging in heart failure (HF) subjects and to assess the differences between patients with ischaemic and non-ischaemic HF. Methods and results Results of quantitative analyses of 123I-mIBG myocardial SPECT, alone and in combination with 99mTc tetrofosmin SPECT, were studied in 619 ischaemic (I) and 319 non-ischaemic (NI) HF subjects from the ADMIRE-HF trial. Cardiac and all-cause mortality data for 2-year follow-up were collected in the extension study (ADMIRE-HFX) and were examined in relation to extent and severity of voxel-based defects, the number of myocardial segments with significant dysinnervation (derived score ≥2), and 123I-mIBG/99mTc tetrofosmin mismatch quantitation. Cox proportional hazards and survival analyses were used to identify higher and lower risk groups and to define thresholds for optimal discrimination between the two. Two-year all-cause and cardiac mortality were not significantly different between IHF and NIHF subjects. Mortality was higher in patients with dysinnervation involving >50% of the myocardium. Highest cardiac mortality risk for IHF subjects was seen with perfusion defects involving 20–40% of the myocardium. By comparison, NIHF subjects with smaller perfusion abnormalities (

The purpose of this study was to develop and validate new approaches to quantitative MIBG myocardial SPECT imaging in heart failure (HF) subjects. Quantitative MIBG myocardial SPECT analysis methods, alone and in conjunction with 99mTc-tetrofosmin perfusion SPECT, were adapted from previously validated techniques for the analysis of SPECT and PET perfusion imaging. To account for underestimation of MIBG defect severity in subjects with global reduction in uptake, a mixed reference database based on planar heart/mediastinum (H/M) ratio categories was used. Extent and severity of voxel-based defects and number of myocardial segments with significant dysinnervation (derived score ≥2) were determined. MIBG/99mTc-tetrofosmin mismatch was quantified using regions with preserved innervation as the reference for scaling 99mTc-tetrofosmin voxel maps. Quantification techniques were tested on studies of 619 ischemic (I) and 319 non-ischemic (NI) HF subjects. Using all analytical techniques, IHF subjects had significantly greater and more severe MIBG SPECT abnormalities compared with NIHF subjects. Innervation/perfusion mismatches were also larger in IHF subjects. Findings were consistent between voxel- and myocardial-segment-based quantitation methods. Multiple objective methods for quantitation of MIBG SPECT imaging studies provided internally consistent results for distinguishing the different patterns of uptake between IHF and NIHF subjects.