Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology Assessment of the area at risk after acute myocardial infarction using 123I-MIBG SPECT: Comparison with the angiographic APPROACH-score Fabien Vauchot, MD, PhD, Fayçal Ben Bouallègue, MD, PhD, Christophe Hedon, MD, Christophe Piot, MD, PhD, François Roubille, MD, PhD, Denis Mariano-Goulart, MD, PhD Department of Nuclear Medicine, Montpellier University Hospital, Montpellier cedex 5, France Institution Picture/Logo Optional Copyright American Society of Nuclear Cardiology

BACKGROUND 1- Area at risk (AAR) is defined as the physiological area with ischemic stress induced by the acute occlusion of a coronary artery An accurate assessment of the AAR is crucial to study the myocardial salvage, expressed as a reduction in the ratio of infarct size to AAR 2- The modified APPROACH score allows a retrospective analysis of AAR based on clinical angiographic results 3-Alterations in myocardial sympathetic activity can be assessed by imaging with 123 I- MIBG cardiac scintigraphy 4- Cardiac 123 I-MIBG SPECT performed soon after treatment of ST elevation myocardial infarction (STEMI) in a cardiac intensive care unit is likely to be a tool for AAR assessment that is based on the sensitivity of neuronal cells to ischemia only and does not assume any anatomical hypothesis Copyright American Society of Nuclear Cardiology Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology

METHODS A. Study type: Prospective study B. Study subjects: January 2014 ‒ May 2015, all patients with STEMI referred to the intensive care unit of the department of cardiology of Montpellier University Hospital for primary coronary intervention Exclusion criteria: previous history of myocardial infarction, heart failure, dilated or hypertrophic cardiomyopathy, ventricular arrhythmias, Parkinson’s disease, psychiatric diseases, or medication with a known potential effect on MIBG uptake before admission to the department of cardiology Twenty patients were excluded from the study because of their culprit lesion topography: diagonal, obtuse marginal, posterior descending artery and posterolateral artery Three more patients were excluded because of collateral flow C. Study endpoints: Primary: Correlation between scintigraphic and angiographic score for occluded arteries Secondary: No correlation for sub-occluded arteries D. Study variables: AAR in % of the left ventricle estimates with angiographic score (ApAR) and scintigraphic score (MAR) Copyright American Society of Nuclear Cardiology Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology

RESULTS Copyright American Society of Nuclear Cardiology Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology Scatterplots between APPROACH-score and 123 I-MIBG hypofixation area for occluded culprit artery. (MAR: 123 I- MIBG area at risk, ApAR: anatomical area at risk with modified APPROACH-score, LV: left ventricle) Bland-Altman analysis comparing APPROACH-score and 123 I-MIBG hypofixation area for patients with occluded artery. (With MAR: 123 I-MIBG area at risk, ApAR: anatomical area at risk with modified APPROACH-score, LV: left ventricle)

RESULTS Copyright American Society of Nuclear Cardiology Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology Scatterplots between APPROACH-score and 123 I-MIBG hypofixation area for sub-occluded culprit artery. (MAR: 123 I-MIBG area at risk, ApAR : anatomical area at risk with modified APPROACH-score, LV: left ventricle) Bland-Altman analysis comparing APPROACH score and 123 I-MIBG hypofixation area for patients with sub- occluded artery. (With MAR: 123 I-MIBG area at risk, ApAR : anatomical area at risk with modified APPROACH-score, LV: left ventricle)

CONCLUSIONS 1. For patient with occluded arteries: 123 I-MIBG cardiac scintigraphy: alternative for AAR assessment 2. For patients with sub-occluded arteries: Further studies are needed including CMR in order to validate AAR assessment with a scintigraphic method Copyright American Society of Nuclear Cardiology Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology