Vergleich von relativer ¹⁸FDG-Aufnahme mit metabolischer Rate (MRGlukose) im Myokard bei KHK, klassifiziert mit ^99mTc-MIBI

Zusammenfassung

Ziel: Sind a) die typischen Perfusions-/Stoffwechsel-Befundmuster (Match, Mismatch) aus dem Vergleich ^99mTc-MIBI-/¹⁸FDG-Speicherung (normiert auf das Perfusionsmaximum) auch für ^99mTc-MIBI-/regionale MRGlukose (Glu; Auswertung nach Patlak) zu finden und ist b) rMGIu im Perfusionsmaximum für alle Schweregrade der KHK im Richtwertebereich? Methoden: Bei 55 Patienten mit KHK wurden die relative myokardiale Speicherung von ^99mTc-MIBI (in Ruhe; SPECT) und von ¹⁸FDG (nach Glukoseladung, PET) vergleichend zu rMRGIu (in fxmol/100 g/min) in je 13 Segmenten des linken Ventrikels (insgesamt 715 Segmente) bestimmt. Ergebnisse: Die rMRGIu zeigte Streubreiten von bis zu 51 %. Sie nahm in der Reihenfolge normal (52,7 ± 27,3 fxmol/100 g/min), mismatch (45,3 ± 17,3), intermediär (35,2 ± 12,4) nach match (»avital«, 26,7 ± 13,3) signifikant (p <0,01) ab. In 26% der Perfusionsmaxima war MIRGIu <40 fxmol/ 100 g/min, darunter nur bei fünf Dreigefäßerkrankungen (von 28) <30 fxmol. Die Serumglukosewerte zeigten bei drei dieser fünf Patienten eine ungenügende Antwort auf die orale Glukosebelastung. Schlußfolgerung: rMIRGIu erbrachte bei KHK die gleichen Fluß/Stoffwechsel-Befundmuster wie die relative FDG-Speicherung. Der größere Aufwand für die Berechnung von rMRGIu ergab keinen diagnostischen Vorteil. Das Perfusionsmaximum (100% MIBI) als Bezugswert für FDG (= 100% FDG) war auch bei euglykämisch eingestellten Patienten mit Dreigefäßerkrankungen verläßlich.

Summary

Aim: Are i) typical patterns of perfusion/metabolism (match, mismatch), gained from relative ^99mTc-MIBI vs relative ¹⁸FDG uptake (normalized to the perfusion maximum) obtainable also vs absolute MRGIu and is ii) rMRGIu in the segment of maximum perfusion (MIBI = 100%) within the normal range for all degrees of coronary artery disease (CAD)? Methods: In 55 non-diabetic patients with CAD, relative myocardial perfusion (^99mTc MIBI SPECT at rest) and relative ¹⁸FDG uptake (PET after glucose load) were used to separate for various flow/metabolism constellations. In addition, regional glucose metabolic rate (rMRGIu in ixmol/ 100 g/min; dynamic-graphic analysis from Gambhir/Patlak) was determined in 13 segments of the left ventricle each (i. e., in a total of 715 segments). Results: rMRGIu revealed wide standard deviations (up to 51%). It decreased from normal (52.7 ± 27.3 (xmol/100 g/min), mismatch (45.3 ± 17.3) and intermediate (35.2 ± 12.4) to match (»non viable«; 26.7 ± 13.3) significantly (p <0.01). In 26% of the perfusion maxima, MRGIu was <40 (xmol/100 g/min. Out of these, only in five patients (of 28) with 3-vessel disease, it was even smaller (<30 (xmol). In three out of the latter, glucose blood levels were below euglycemia. Conclusion: rMRGIu in CAD revealed an identical perfusion/metabolism pattern as relative ¹⁸FDG uptake. Thus, the higher efforts employed to compute rMRGIu do not yield diagnostic advantage. The segmental perfusion maximum, used for normalization of relative ¹⁸FDG uptake (100% MIBI uptake = 100% FDG uptake) was reliable in euglycemic patients even with 3-vessel disease.

Schlüsselwörter

Stoffwechselrate Glukose (rMRGIu) - ¹⁸FDG-PET - ^99mTc-MIBI-SPECT - CAD

Keywords

Metabolic rate glucose (rMRGIu) - ¹⁸FDG-PET - ^99mTc-MIBI-SPECT - CAD

• LITERATUR

• 1 Altehoefer C, Kaiser HJ, Dörr R. et al. Fluo-rine-18 deoxyglucose PET for assessment of viable myocardium in perfusion defects in ^99mTc MIBI SPET: a comparative study in patients with coronary artery disease. Eur J Nucl Med 1992; 19: 334-42.
• 2 Altehoefer C, vom Dahl J, Biederman M. et al. Significance of defect severity in technetium-99m-MIBI SPET at rest to assess myocardial viability: comparison with fluorine-18-FDG PET. J Nucl Med 1994; 35: 569-74.
• 3 Baer FM, Voth E, Schneider ChA. et al. Comparison of low-dose dobutamine-gradient echo MRI and PET with 18-F fluorodeoxyglu-cose in patients with chronic coronary artery disease. Circulation 1995; 91: 1006-15.
• 4 Choi Y, Hawkins RA, Huang SC. et al. Parametric images of myocardial metabolic rate of glucose generated from dynamic cardiac PET and 2-18F-Fluoro-2-deoxy-D-glucose studies. JNucl Med 1991; 32: 733-8.
• 5 Choi Y, Brunken RC, Hawkins RA. et al. Factors affecting myocardial 2-(F-18)fluoro-2-deoxy-D-glucose uptake in PET studies of normal humans. Eur J Nucl Med 1993; 20: 308-18.
• 6 Gambhir SS, Schwaiger M, Huang SC. et al. Simple noninvasive quantification method for measuring myocardial glucose utilization in humans employing PET and F-18 Deoxyglucose. J Nucl Med 1989; 30: 359-66.
• 7 Hicks RJ, Herman WH, Kalf V. et al. Quantitative evaluation of regional substrate metabolism in the human heart by PET. J Am Coll Cardiol 1991; 18: 101-11.
• 8 Knuuti MJ, Nuutila P, Ruotsalainen U. et al. Euglycemic hyperinsulinemic clamp and oral glucose load in stimulating myocardial glucose utilization during PET. J Nucl Med 1992; 33: 1255-62.
• 9 Knuuti MJ, Nuutila P, Ruosalainen U. et al. The value of quantitative analysis of glucose utilization in detection of myocardial viability by PET. J Nucl Med 1993; 34: 2068-75.
• 10 Knapp WH. Möglichkeiten und Grenzen der Myokardperfusionsszintigraphie für die Vitalitätsdiagnostik. Nucl-Med 1995; 34: 118-26.
• 11 Lucignani G, Paolini G, Landoni C. et al. Presurgical identification of hibernating myocardium by combined use of technetium-99m hexakis-MIBI SPET and fluorine-18-2-deoxy-D-glucose PET in patients with coronary artery disease. Eur J Nucl Med 1992; 19: 874-81.
• 12 Ohtake T, Yokoyama I, Watanabe T. et al. Myocardial glucose metabolism in noninsulin-dependent diabetes mellitus patients evaluated by FDG-PET. J Nucl Med 1995; 36: 456-63.
• 13 Patlak CS, Blasberg RG. Graphical evaluation of blood-to-brain transfer constants from multiple-time uptake data. J Cerebr Blood Flow Metab 1985; 5: 584-90.
• 14 Perrone-Filardi P, Bararach SL, Dilsizian V. et al. Clinical significance of reduced myocardial glucose uptake in regions with normal blood flow in patients with CAD. J Am Coll Cardiol 1994; 23: 608-16.
• 15 Porenta G, Kuhle W, Czernin J. et al. Semiquantitative assessment of myocardial blood flow and viability using polar map display of cardiac PET images. J Nucl Med 1992; 33: 1623-31.
• 16 Ratib O, Phelps ME, Huang SC. PET for estimating local myocardial glucose metabolism. J Nucl Med 1982; 23: 577-86.
• 17 Schulz G, vom Dahl J, Kleinhans E, Büll U. Left branch bundle block (LBBB) causes reverse flow/FDG mismatch in severe left ventricular descending artery (LAD) disease (abstract). Eur J Nucl Med 1995; 22: 829.
• 18 Schwaiger M, Hicks R. The clinical role of metabolic imaging of the heart by PET. J Nucl Med 1991; 32: 567-78.
• 19 Vanoverschelde JLJ, Melin JA, Bol A. et al. Regional oxidative metabolism in patients after recovery from reperfused anterior myocardial infarction. Relation to regional blood flow and glucose uptake. Circulation 1992; 85: 9-21.
• 20 vom Dahl J, Herrmann WH, Hicks RJ. et al. Myocardial glucose uptake in patients with insulin-dependent diabetes mellitus assessed quantitatively by dynamic PET. Circulation 1993; 88: 395-404.
• 21 vom Dahl J, Altehoefer C, Sheehan FH. et al. Recovery of regional left ventricular dysfunction following coronary revascularization: impact of myocardial viability assessed by nuclear imaging and of vessel patency at follow-up angiography. J Am Coll Cardiol (in press).