Re-Injektion von ²⁰¹TI bei Postinfarktpatienten zur besseren Abgrenzung von Narbe und Ischämies

Zusammenfassung

Bei Postinfarktpatienten wurde der Wert zusätzlicher, nach Re-Injektion von ²⁰¹TI durchgeführter Aufnahmen zur besseren Erfassung von ischämischem Myokard untersucht. 40 Patienten wurde 24 h nach Belastung 40 MBq ²⁰¹TI re- injiziert und 1 h später zusätzliche SPECT-Aufnahmen angefertigt. Die Quantifizierung der Defektgrößen zeigte bei 18 Patienten eine weitere Abnahme der 4 h-Re-Distributionsdefekte um mehr als 30%. Der Vergleich mit klinischen, elektrokardiographischen und nuklearmedizinischen Parametern ergab, daß diese keine ausreichend präzise Vorhersage über den zu erwartenden Effekt nach Re-Injektion erlauben. Von 22 koronarangiographierten Patienten zeigten alle 11 Patienten mit kollateralisierten Verschlüssen eine Verkleinerung des ReDistributionsdefekts von > 20%, während alle Patienten mit Verschlüssen ohne distale Kollateralisation (5/5) Veränderungen von <20% aufwiesen. Dies bestätigt, daß es sich bei Myokard mit verbesserter Thallium-Aufnahme nach Re-Injektion um ischämisches, aber vitales Myokard handelt.

Summary

In patients with earlier myocardial infarction the value of additional imaging after reinjection of ²⁰¹TI for better detection of ischemic myocardium was assessed. In 40 patients 40 MBq ²⁰¹TI were reinjected 24 h after stress and additional SPECT was performed 1 h later. Quantification of defect sizes showed a further reduction of 4 h redistribution defects by more than 30% in 18 patients. Comparison with clinical, electrocardiographic and scintigraphic parameters showed that none of these was sufficiently accurate for predicting additional thallium uptake after reinjection. In 22 patients with coronary angiography all 11 patients with collateralized occlusions of a coronary artery showed a reduction of the 4 h redistribution defect by > 20%, whereas all patients (5/5) with occlusions without distal collateralization had changes <20%. This demonstrates that an improved thallium uptake after reinjection is typical of ischemic but vital myocardium.

Schlüsselwörter

²⁰¹TI-Myokardszintigraphie - Re-Injektion - Myokardvitalität

Key words

²⁰¹TI myocardial scintigraphy - reinjection - myocardial viability

• Literatur

• 1 Berger BC, Watson DD, Burwell LR. et al. Redistribution of thallium at rest in patients with stable and unstable angina and the effect of coronary bypass surgery. Circulation 1979; 60: 1114-25.
• 2 Blood DK, McCarthy DM, Sciacca RR. et al. Comparison of single-dose and double- dose²⁰¹TI myocardial perfusion scintigraphy for the detection of coronary artery disease and prior myocardial infarction. Circulation 1981; 58: 777-77.
• 3 Bonow RO, Dilsizian V, Cuocolo A. et al. Identification of viable myocardium in patients with chronic coronary artery disease and left ventricular dysfunction. Comparison of thallium scintigraphy with reinjection and PET imaging with 18-fluorodeoxyglucose. Circulation 1991; 83: 26-37.
• 4 Botsch H. Nuklearmedizinische Methoden in der kardiologischen Diagnostik. Internist 1990; 31: 333-7.
• 5 Botsch H, Heil M, Weidemann H. et al. Differenzierung von Ischämie und Narbe im Thallium-Szintigramm durch die 24-Stun- den-Spätaufnahme. Nucl-Med 1989; 28: A 80.
• 6 Brunken R, Kottou S, Nienaber C. et al. PET detection of viable tissue in myocardial segments with persistent defects at ²⁰¹TI SPECT. Radiology 1989; 172: 65-73.
• 7 Brunken RC, Vaghaiwalla F, Hawkins RA. et al. Positron tomography detects glucose metabolism in segments with 24 hour tomographic thallium defects. Circulation 1988; 78: 91.
• 8 Buddinger TF, Pohost GM, Bischoff P. ²⁰¹TI integral blood concentration over 2 hours explains persistent defects in patients with no evidence of MI by ECG. Circulation 1987; 76: 64.
• 9 Clausen M, Weller R, Henze E. et al. Differenzierende Darstellung und Quantifizierung der Myokardnarbe und der Belastungsischämie in Polarkoordinaten für die Myokard-ECT. Klinische und technische Aspekte. NUC-Comp 1988; 19: 50-2.
• 10 Cloninger KG, De Puey EG, Garcia E. et al. Incomplete redistribution in delayed ²⁰¹TI single photon emission computed tomography (SPECT) images: overestimation of myocardial scarring. J Am Coll Cardiol 1988; 12: 955-63.
• 11 Dilsizian V, Rocco TP, Freedman NMT. et al. Enhanced detection of ischemic but viable myocardium by the reinjection of thallium after stress - redistribution imaging. N Engl J Med 1990; 323: 141-6.
• 12 Dilsizian V, Smeltzer WR, Freedman NM. et al. Thallium reinjection after stress-redistribution imaging. Does 24-hour delayed imaging after reinjection enhance detection of viable myocardium? Circulation 1991; 83: 1247-55.
• 13 Gewirz H, Beller GA, Strauss HW. Transient defects of resting thallium scans in patients with coronary artery disease. Circulation 1979; 59: 707-13.
• 14 Gibson RS, Watson DD, Craddock GB. et al. Prediction of cardiac events after uncomplicated myocardial infarction: a prospective study comparing predischarge exercise ²⁰¹TI scintigraphy and coronary angiography. Circulation 1983; 68: 321-36.
• 15 Gibson RS, Watson DD, Taylor GJ. Prospective assessment of regional myocardial perfusion before and after coronary revascularisation surgery by quantitative ²⁰¹TI tomography. J Am Coll Cardiol 1983; 03: 804-15.
• 16 Gutmann J, Berman DS, Freeman M. et al. Time of completed redistribution of ²⁰¹TI in exercise myocardial scintigraphy: relationship to the degree of coronary artery stenosis. Am Heart J 1985; 106: 989-95.
• 17 Haerten RL, Hernandez T. Einzelphoto- nen-Emissionscomputertomographie (SPECT): Grundlagen, Technik und klinische Anwendung. Electromedica 1984; 25: 66-80.
• 18 Kayden DS, Sigal SL, Soufer R. et al. 24- hour planar ²⁰¹TI delayed imaging: is reinjection neccssary?. Circulation 1989; 80: 377.
• 19 Kiat H, Berman DS, Maddahi J. et al. Late reversibility of tomographic myocardial ²⁰¹TI defects: an accurate marker of myocardial viability. J Am Coll Cardiol 1988; 12: 1456-63.
• 20 Kiat H, Friedman JD, Wang FP. et al. Frequency of late reversibility in stress- redistribution ²⁰¹TI SPECT using an early reinjection protocol. Am Heart J 1991; 122: 613-9.
• 21 Liu P, Kiess MC, Okada RD. et al. The persistent defect on exercise thallium imaging and its fate after myocardial revascularization: does it represent scar or ischemia?. Am Heart J 1985; 110: 996-1000.
• 22 Pohost GM, Zir LM, Moore R. et al. Differentiation of transiently ischemic from in- farcted myocardium by serial imaging after a single dose of ²⁰¹TI. Circulation 1977; 55: 294-302.
• 23 Ritchie JL, Trobough GB, Hamilton GW. et al. Myocardial imaging with ²⁰¹TI at rest and during exercise: comparison with coronary arteriography and resting and stress electrocardiography. Circulation 1977; 56: 66-71.
• 24 Schober O, Häsfeld M, Matheja P. et al. Thallium reinjection vs redistribution in severe stenosis of coronary arteries dependent on the collateralization. Eur J Nucl Med 1991; 17: 538.
• 25 Tamaki N, Ohtani H, Yonekura Y. et al. Relation of left ventricular perfusion and wall motion with metabolic activity in persistent defects on ²⁰¹TI tomography in health myocardial infarction. Am J Cardiol 1990; 62: 202-8.
• 26 Tamaki N, Ohtani H, Yamashita K. et al. Metabolic activity in the areas of new fill-in after ²⁰¹TI reinjection: comparison with positron emission tomographie using fluo- rine-18-deoxyglucose. J Nucl Med 1991; 32: 673-8.
• 27 Tillisch J, Brunken R, Marshall R. et al. Reversibility of cardiac wall-motion abnormalities predicted by positron tomography. N Engl J 1986; 314: 884-8.
• 28 Wilson RA, Sullivan PJ, Okada R. et al. The effect of eating on thallium myocardial imaging. Chest 1986; 89: 195-8.
• 29 Wilson WW, Gibson RS, Nygoard TW. et al. Acute myocardial infarction associated with single vessel coronary artery disease: an analysis of clinical outcome and the prognostic importance of vessel patency and residual ischemic myocardium. J Am Coll Cardiol 1988; 11: 223-33.
• 30 Yang LD, Berman DS, Kiat H. et al. The frequency of late reversibility in SPECT ^2ü1TI stress-redistribution studies. J Am Coll Cardiol 1990; 15: 334-40.