Nuklearmedizinische Ischämiediagnostik: Technischer Stand Tl-201 SPE(C)T Tc-99m-MIBI Tc-99m-Tetrofosmin [N-13]NH3 PET [F-18]FDG Emissionsthomographie

STRESS REST STRESS REST STRESS REST Fall 5 SHORT AXIS APEX BASE VERTICAL LONG AXIS STRESS SEPTAL LATERAL REST HORIZONTAL LONG AXIS STRESS INFERIOR ANTERIOR REST Fall 5

Semiquantitative-Visual Analysis Apical Mid Basal Mid 1 6 5 4 3 2 7 8 12 11 9 10 13 14 15 16 18 17 19 20 SSS =  Segmental Stress Score Segmental Scoring 0 = Normal 1 = Equivocal 2 = Moderate 3 = Severe 4 = Absent Uptake A range of options is available for reporting the diagnostic and prognostic information obtained through MPI. Simply reporting the study results as normal or abnormal, although useful diagnostically, is too simplistic to provide the maximum data that can be obtained from the study for both diagnosis and prognosis. Interpretation of the findings and information on the degree of abnormality are also necessary. The degree of abnormality can be described in several ways. One of the more commonly used methods, and the one used in many studies on the prognostic use of MPI, is a semiquantitative-visual analysis that divides the three orthogonal MPI views into 20 segments, as shown in the slide.1 Each segment is scored according to a 5-point scale that rates normal uptake of radioactivity in each segment as 0, with a score of 4 indicating absent uptake. Scores of the stress images are totaled to produce the summed stress score (SSS), which characterizes the extent and severity of coronary disease in a semiquantitative fashion. Summed stress scores <4 are classified as normal, with scores from 4 to 8 considered mildly abnormal. Scores from 9-13 are moderately abnormal and scores >13 are severely abnormal. Additional scores can be determined. The summed rest score (SRS) represents defects present at rest and reflects extent and severity of infarction. The summed difference score (SDS), which is the difference between the SSS and the SRS, represents extent and severity of stress-induced ischemia. Other scoring systems use fewer segments or other methods of scoring and have been validated clinically. This method is shown to establish the criteria used in some important studies that have documented prognostic value and to show the potential utility in everyday practice. Summed stress scores have been found to be one of the most important prognostic markers, as they represent the extent and severity of coronary disease. 1. Hachamovitch R, Berman DS, Shaw LJ, et al. Incremental prognostic value of myocardial perfusion single photon emission computed tomography for the prediction of cardiac death: differential stratification for risk of cardiac death and myocardial infarction. Circulation. 1998;97:535-543. SRS =  Segmental Rest Score SDS = SSS - SRS Hachamovitch R, et al. Circulation. 1998;97:535-543.

Functional Imaging: ECG-Gated Myocardial SPECT Projection Data Sets (8-16 Intervals Each) An important feature of SPECT MPI procedures is the ability to obtain functional data without requiring an additional study. Gated SPECT is performed at the same time as perfusion data are accumulated, using the same imaging equipment and the same dose of imaging agent.1 ECG electrodes are placed on the patient, and ECG data are accumulated at the same time counts are accumulated for the perfusion images. The difference in the procedures is that the gated data are acquired at each projection angle and the data are related to the specific portion of the cardiac cycle during which it was collected. The data are then processed and reconstructed using computer programs into a SPECT volume image for each portion of the cardiac cycle that can be processed to calculate functional volumes and generate wall motion images that can be viewed on a computer screen. 1. Germano G, Berman DS. Acquisition and processing for gated perfusion SPECT: technical aspects. In: Germano G, Berman DS. Clinical Gated Cardiac SPECT. Armonk, Y: Futura Publishing Company, Inc; 1999:94. Tomographic 180° SPECT short axis image sets Acquisition (after reconstruction & reorientation) Reprinted with permission from Clinical Gated Cardiac SPECT. Germano G, Berman DS. Copyright 1999. Futura Publishing Company, Inc, Armonk, NY 10504-0418.

Myokard Perfusion und Wandbewegungsanalyse

A: Normal B: RIVA-Stenose C: Z. n. HWI

Untersuchung der Gewebsvitalität Ischämie

Nuklearmedizinische Ischämiediagnostik: Klinische Ergebnisse Nachweis Stenosen ≥ 50% (Vasodilator/Basis -SPET): Sensitivität Spezifität 89% (N = 1963) 75% (N = 529)

Nuklearmedizinische Ischämiediagnostik: Klinische Ergebnisse Prognose (MI, Herztod) bei negativer Myokard-SPET (B/R): < 0,5% / a (N=5183) (Prospektive Studie, Dt 642 +/- 226 d, R Hachamovitch et al 1998) EKG-gesteuerte Myokard-SPET : Steigerung des prognostischen Werts für Herztod durch LVEF (T Sharir et al 2001)

Nuklearmedizinische Ischämiediagnostik: Klinische Ergebnisse Differenzierung Vitalität / Narbe Prädiktion Verbesserung der regionalen LV-Funktion: Sensitivität, Spezifität 70 - 90 % (PET > SPET bei LVEF < 30 %)

Stress Echo vs SPECT SPET Stress Echo Höhere technische Erfolgsrate Höhere Sensitivität (bes.1-G-KHK) Ischämienachweis unproblematisch bei Wandbeweg.-störung in Ruhe Bessere Datenlage bzgl. Prognosewert Stress Echo Hohe Spezifität Mehr anatomische Information Einfacher und schneller Zugang Geringere Kosten The imaging modalities most commonly used in evaluating patients for CAD are stress echocardiography and stress SPECT. The recent ACC/AHA/ACP-ASIM guidelines for chronic stable angina reviewed these and other noninvasive tests for CAD and compared stress echocardiography and stress SPECT.1 Stress echocardiography is reported to have good specificity. The procedure is considered versatile in providing a more extensive evaluation of cardiac anatomy and function than does stress SPECT. Stress echocardiography is available in many physician offices, making it more convenient and available to physicians and patients. Stress echocardiography is available at lower cost than stress SPECT. Stress SPECT is associated with a higher technical success rate than stress echocardiography and is not dependent on operator expertise. The sensitivity of stress SPECT is higher than that of stress echocardiography, particularly for single-vessel disease. SPECT also has better accuracy in evaluating ischemia when rest left ventricular wall motion is abnormal. The prognostic role of SPECT is defined by more extensive published literature that presents a consistent picture of reproducible clinical utility. Gibbons RJ, Chatterjee K, Daley J, et al. ACC/AHA/ACP-ASIM guidelines for the management of patients with chronic stable angina: executive summary and recommendations. Circulation. 1999;99:2829-2848. Adapted from Gibbons RJ, et al. Circulation. 1999;99:2829-2848.

Imaging Modality: Stress Echo Image Quality All studies read by 4 blinded/experienced MD sonographers 100% 100% 50% Agreement 83% Patients 80% 74% 40% Agreement, % 60% 55% 30% 31% Patients, % 43% 27% 40% 23% 20% Reproducibility and reliability of results are determinants of accuracy that reflect the results in actual practice. Reproducibility may be a function of location of testing and experience of the interpreter. One study illustrates the effect of reproducibility on stress echocardiography images.1 Stress echocardiography has been noted to be operator dependent and associated with image quality problems. In this interinstitutional study, 150 stress echocardiography studies were reviewed by 4 experienced, blinded sonographers; studies were classified according to image quality and the interpretations compared. Observer interpretations agreed in all cases in which studies were rated as excellent. Interpretation agreement decreased with decreasing study quality. Image quality was considered to be unacceptable to poor in 60% of the studies; in these studies agreement among observers was 43-74% indicating a large amount of variability even among experienced observers. Only 9% of studies were rated as being of excellent quality in which there was 100% agreement on interpretation. Hoffmann R, Lethen H, Marwick T, et al. Analysis of interinstitutional observer agreement in interpretation of dobutamine stress echocardiograms. J Am Coll Cardiol. 1996;27:330-336. 20% 10% 10% 9% 0% 0% 40% 60% Excellent Good Fair Poor Unacceptable Study Quality Adapted from Hoffman R, et al. J Am Coll Cardiol. 1996;27:330-336.

Nuklearmedizinische Ischämiediagnostik: Indikationen II. Chronische Syndrome Unsichere Diagnose KHK: mittl. P Myo-SPET Bel/Ruhe (neg. Bel-EKG, typ. Ang oder umgekehrt) Hämodyn. Signifikanz v. Stenose(n) nach Myo-SPET Bel/Ruhe Coronarangiographie, Nachweis der führenden Stenose

Nuklearmedizinische Ischämiediagnostik: Indikationen IV. Risiko-Stratifizierung nach Infarkt Myo-SPET Vasodilat.! LBBB, Schrittmacher „ „ „ Präoperativ bei mittl. p für KHK Hypertensive HK Diabetes mellitus