Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology Association between non-perfusion parameters and presence of ischemia in gated-SPECT myocardial perfusion imaging studies Amalia Peix*, Lázaro O. Cabrera*, Kenia Padrón*, Lydia Rodríguez*, Jesús Fernández*, Giselle López*, Regla Carrillo*, Erick Mena*, Yoel Fernández*, Maurizio Dondi†, Diana Páez† *Institute of Cardiology, Havana, Cuba †Nuclear Medicine and Diagnostic Imaging Section, Division of Human Health, International Atomic Energy Agency, Vienna, Austria INSTITUTO DE CARDIOLOGÍA Y CIRUGÍA CARDIOVASCULAR, LA HABANA, CUBA Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology BACKGROUND 1- Combined assessment of perfusion and function improves diagnostic and prognostic power of gated-SPECT in patients with coronary artery disease 2- However, there is insufficient information regarding the comparison of left ventricular (LV) parameters among different groups of patients with or without ischemia, particularly under resting conditions 3- Specifically, are there resting differences in LV functional parameters such as end-diastolic volume (EDV), end-systolic volume (ESV), LVEF or dyssynergy in patients that have evidence of stress-induced ischemia? 4-The aim of this study was to investigate whether the presence of stress-induced ischemia is associated with abnormal resting LV function and intraventricular dyssynchrony Copyright American Society of Nuclear Cardiology

METHODS Study type:(Select all that apply) Study subjects: Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology METHODS Study type:(Select all that apply) Observational study Study subjects: Patients (101, mean age: 60±9 years, 68% male), who were referred to the Nuclear Medicine Department of the Institute of Cardiology from April 2011 to April 2014 with known or suspected CAD, able to exercise on treadmill or bicycle, with an intermediate or high risk Duke treadmill score, underwent a 99mTc-MIBI gated-SPECT (two-day protocol: exercise stress/rest), including left ventricular dyssynchrony assessment by phase analysis These patients were divided in three groups: those with stress-induced ischemia (Group 1, 58 patients), those with normal scans (Group 2, 28 patients), and those with scar but no ischemia (Group 3, 15 patients) Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology RESULTS In Group 1 patients, the LVEF was 65±11% at rest, but decreased to 59±12% post-stress (p<0.0001). In Group 2, the LVEF was 72±8% at rest, and decreased slightly to 69±9% post-stress (p=0.0.02). In Group 3, the LVEF was 47±15% at rest and decreased to 41±12% post-stress (p=0.01). The mean ΔLVEF (LVEF at stress – LVEF at rest) was higher in Group 1 compared to Group 2 (-5.54±6.24% vs. -2.46±5.56%, respectively, p=0.02). Group 3 patients also had higher values, similar to Group 1: -6.47±8.82%. ΔLVEF values greater than minus 5%, which was previously defined as post-stress myocardial stunning, were more frequently observed in Group 1 patients: 30 out of 58 patients (52%) vs. 4 out of 15 patients (26%) in Group 3 With respect to intraventricular synchrony parameters, phase-derived standard deviation (PSD) values were not significantly different between rest and post-stress: Group 1: 26.0±13.90 vs. 28.2±16.10, and Group 2: 27.2±24.10 vs. 22.9 ± 15.90, respectively. However, the histogram bandwidth (HBW) was higher at rest in Group 1 compared with Group 2 (73.5±47.40 vs. 53.2±29.30, respectively, p=0.04), and the difference became even greater following stress (85.7±70.30 vs. 54.3±35.90, respectively, p=0.02). Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology RESULTS Mean end-diastolic and end-systolic volumes are presented according to the presence or not of ischemia on MPI. Ischemic patients had almost 50% higher resting end-diastolic volumes than patients with normal MPI. Similarly, resting end-systolic volumes were almost twice as high (p<0.0001). End-systolic volume showed a significant difference between rest and early post-stress acquisition (p<0.0001) in Group 1 patients. Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology CONCLUSIONS Baseline resting differences in left ventricular volumes and degree of dyssynchrony are associated with inducible ischemia on gated-SPECT MPI Stress-induced ischemia increases the degree of intraventricular dyssynchrony Copyright American Society of Nuclear Cardiology