Poster: EANM 18 / EP-0509 / Cost-analysis of a new diagnostic strategy in patients with solitary pulmonary nodule: the Italian Tailored Assessment of Lung Indeterminate Accidental Nodule (ITALIAN) multicenter trial by: Evangelista1, L. Pace2, L. Mansi3, E. Mazziotti4, S. Del Vecchio4, G. Pepe5, L. Basso6, S. ANNUNZIATA7, A. Golemi8, A. Chiaravalloti9, R. Galicchio10, L. Guerra11, M. Zuffante12, N. Frega13, V. Rizzo14, A. Lambertini15, A. Cuocolo4, M. Spadafora16; 1Veneto Institute of Oncology IOV - IRCCS, Padova, ITALY, 2Universita di Salerno, Salerno, ITALY, 3Centro Universitario di Ricerca per lo Sviluppo Sostenibile, Napoli-Roma, ITALY, 4Universita degli Studi di Napoli “ Federico II°”, Napoli, ITALY, 5Humanitas Cancer Center, Milano, ITALY, 6SDN – IRCCS, Napoli, ITALY, 7Universita’ Cattolica di Roma, Roma, ITALY, 8Ospedale di Bolzano, Bolzano, ITALY, 9Universita Tor Vergata, Roma, ITALY, 10CROB – IRCCS; Rionero in Vulture, Potenza, ITALY, 11Ospedale San Gerardo – AAST Monza, Monza, ITALY, 12Azienda Universitaria Integrata di Verona, Verona, ITALY, 13Medicina Futura Acerra, Napoli, ITALY, 14Ospedale san Giuseppe Moscati, Avellino, ITALY, 15Universita degli Studi di Bologna, Bologna, ITALY, 16Ospedale del Mare, Napoli, ITALY

Insulin infusion improves myocardial blood flow (MBF) in healthy subjects. Until now, the effect of insulin on myocardial perfusion in type 2 diabetic subjects with coronary artery disease (CAD) has been unknown. We studied the effects of insulin on MBF in ischemic regions evaluated by single-photon emission–computed tomography and coronary angiography and in nonischemic regions in 43 subjects (ages 63 ± 7 years) with type 2 diabetes (HbA1c 7.1 ± 0.9%). MBF was measured at fasting and during a euglycemic-hyperinsulinemic clamp at rest (n = 43) and during adenosine-induced (140 μg · kg−1 · min−1 for 7 min) hyperemia (n = 26) using positron emission tomography and 15O-labeled water. MBF was significantly attenuated in ischemic regions as compared with in nonischemic regions (P < 0.0001) and was increased by insulin as compared with in the fasting state (P < 0.0001). At rest, insulin infusion increased MBF by 13% in ischemic regions (P = 0.043) and 22% in nonischemic regions (P = 0.003). During adenosine infusion, insulin enhanced MBF by 20% (P = 0.018) in ischemic regions and 18% (P = 0.045) in nonischemic regions. In conclusion, insulin infusion improved MBF similarly in ischemic and nonischemic regions in type 2 diabetic subjects with CAD. Consequently, in addition to its metabolic effects, insulin infusion may improve endothelial function and thus increase the threshold for ischemia and partly contribute to the beneficial effects found in clinical trials in these subjects.

Myocardial uptake of 99Tcm-tetrofosmin in vivo is determined by a combination of flow and metabolic status of myocytes. The accumulation of tetrofosmin in the mitochondria is related to their ability to transduce metabolic energy into electronegative membrane potential. Trimetazidine (TMZ), an anti-ischaemic drug, appears to have a metabolic cytoprotective effect related to mitochondrial function, since it does not induce systemic or coronary haemodynamic changes. In this study, we evaluated the effects of TMZ on tetrofosmin uptake in hypoperfused myocardial regions in patients with coronary artery disease (CAD). Twenty-two patients, 14 with previous myocardial infarction (group A) and eight with a history of angina (group B), with angiographically documented CAD were studied. All patients underwent two tetrofosmin SPET studies at rest, before (baseline) and 1 week after TMZ administration (post-TMZ). On quantitative analysis, 131 segments showed less tetrofosmin uptake at baseline. In these segments, tetrofosmin uptake was 51 +/- 13% at baseline and 55 +/- 15% post-TMZ (P < 0.001 vs control). In the 86 hypoperfused segments of group A, tetrofosmin uptake was 48 +/- 14% at baseline and 52 +/- 17% post-TMZ (P < 0.001 vs control). In the 45 hypoperfused segments of group B, tetrofosmin uptake was 56 +/- 9% at baseline and 60 +/- 10% post-TMZ (P < 0.001 vs control). In the remaining 309 segments, no significant difference in tetrofosmin uptake before and after TMZ was observed. In conclusion, our results suggest that TMZ administration may increase myocardial uptake of tetrofosmin in hypoperfused regions at rest in patients with CAD, based on its metabolic effect.