Le FDG dans l évaluation de la viabilité : Quelle place par rapport aux autres traceurs?

Transcription

1 Le FDG dans l évaluation de la viabilité : Quelle place par rapport aux autres traceurs? Pierre-Yves MARIE, Médecine Nucléaire, CHU de Nancy PET Gated-SPECT MRI

2 FDG imaging: effect of dietary status fasting oral glucose hyperinsulinic clamp acipimox

3 FDG imaging: effect of dietary status fasting FFA glucose oral glucose hyperinsulinic clamp acipimox glucose O2 availability O2 availability glucose FFA normal ischemic necrotic Imaging ischemic myocardium FFA normal ischemic necrotic Imaging ischemic + normal

4 Necrotic areas exhibit a dramatic decrease in metabolic activity (decrease in FDG uptake) Sirius red Collagen fibrosis LV 2-months after coronary occlusion in rats Maskali F. J Nucl Cardiol 2005 RV Central Border necrosis zone Remote myocardium 18 F-FDG Injection before sacrifice of 111 In-DTPA 99m Tc-Sestamibi 18 F-FDG µ-imager

5 Necrotic areas exhibit a dramatic decrease in myocardial perfusion (decrease in Sestamibi uptake) Sirius red Collagen fibrosis LV 2-months after coronary occlusion in rats Maskali F. J Nucl Cardiol 2005 RV Central Border necrosis zone Remote myocardium 99m Tc-Sestamibi Injection before sacrifice of 111 In-DTPA 99m Tc-Sestamibi 18 F-FDG µ-imager

6 Delayed retention relates to an enhanced interstitial distribution volume of tracers (decrease in the size of cellular compartment) Sirius red Collagen fibrosis LV 2-months after coronary occlusion in rats Maskali F. J Nucl Cardiol 2005 RV Central Border necrosis zone Remote myocardium 111 In-DTPA Injection before sacrifice of 111 In-DTPA 99m Tc-Sestamibi 18 F-FDG µ-imager

7 Imaging tracers of myocardial viability & necrosis: (i) dependence of MRI extracellular tracers, such as DTPA (Magnevist ), upon local variations in extracellular fluid volume, (ii) gradual decrease in myocardial perfusion between remote, border and necrotic areas for SPECT perfusion tracers, such as Sestamibi, (iii) ischemia-related enhancement in glycolytic metabolism within border zones for 18 F-fluorodeoxyglucose (FDG).

8 µ-imager RV LV FDG + Sestamibi 3-month old coronary occlusion in rat Sirius red Fibrosis 18 F-FDG 99m Tc-Sestamibi

9 Long-axis vertical horizontal basal Short-axis mid-vent. apical Cine MRI SPECT Sestamibi PET FDG

10 Myocardial viability: FDG (glucose metabolism) F18 FDG N13 NH3 Mismatching = viable Matching = not viable

11 Sensitivity and specificity to predict improvement of regional function after revascularisation sensitivity specificity

12 Prédiction de l amélioration de la contractilité segmentaire après revascularisation Comparaisons chez les mêmes patients SPECT FDG-PET IRM (Ga++) Sensibilité 80-90% 90-95% 85%? Spécificité 55-65% 55-65% 60%?

13 Sensitivity and specificity for prediction of reversible segmental dysfunction after revascularisation sensitivity specificity Tl rest redistribution Tl stress redis. reinj. Sestamibi rest FDG/flow PET Pooled data

14 Slart RH, and Coll. Added value of attenuation-corrected Tc-99m tetrofosmin SPECT for the detection of myocardial viability: comparison with FDG SPECT. J Nucl Cardiol. 2004;11: Consecutive patients (n = 33) with CAD and LV dysfunction. Noncorrected and attenuation-corrected Tc-99m tetrofosmin SPECT were compared with the FDG images (reference for viability). Noncorrected Attenuationcorrected

15 Long-axis vertical horizontal basal Short-axis mid-vent. apical C.IRM SPECT Sestamibi + nitrés PET FDG IRM Ga++

16 Short-axis SPECT G-SPECT Sestamibi + nitrés apical mid-vent. basal Long-axis horizontal vertical

17 Evaluation de la viabilité Prédiction de l amélioration de la contractilité segmentaire après revascularisation Seuil de détection de la viabilité 100% SPECT Echographie PET-scan IRM dobutamine FDG (Ga++) Sensibilité 80-90% 60-70% 90-95% 85%? Spécificité 55-65% 80-90% 55-65% 60%? 65% 50% 0% DOBU SPECT

18 Myocardial Perfusion SPECT imaging AZ VUB

19 Effect of low dose dobutamine in infarct patient Baseline LVEF= 46% Dobutamine 10 mcg/kg/min LVEF= 65% AZ VUB

20 Effect of low dose dobutamine in infarct patient baseline Dobutamine 10 mcg/kg/min

21 Allman KC, and Coll. Myocardial viability testing and impact of revascularization on prognosis in patients with coronary artery disease and left ventricular dysfunction: a meta-analysis. J Am Coll Cardiol. 2002;39: viability studies reporting patient survival using Tl-201 imaging, FDG or dobutamine echocardiography. In patients with viability and comared with medical therapy, revascularization was associated with 79.6% reduction in annual mortality (16% vs. 3.2%) Decrease in mortality related to revascularization of viable segments. There was no difference for predicting revascularization benefit between the three techniques.

22 Long-axis vertical horizontal basal Short-axis mid-vent. apical C.IRM SPECT Sestamibi + nitrés PET FDG IRM Ga++

23 Myocardial viability: FDG (glucose metabolism) F18 FDG N13 NH3 Mismatching = viable Matching = not viable