Hybrid Imaging Improving Nuclear Cardiology Practice

Transcription

1 Lippincott Williams & Wilkins, - Nuclear Medicine teaching File, 2009 Hybrid Imaging Improving Nuclear Cardiology Practice João V. Vitola, MD, PhD Cardiologist and Nuclear Medicine Physician Quanta Diagnostico Nuclear Curitiba - Brazil DISCLOSURES Honorarium Research and Conferences in Nuclear Cardiology BMS, CVT, Astellas, Pgx Health/Forest laboratories, Lantheus Medical Imaging International Atomic Energy Agency Royalties Publications in Nuclear Cardiology Springer-Verlag-Nuclear Cardiology and Correlative Imaging: a teaching file, NY, 2004

2 Improving Nuclear Cardiology Practice Recognizing and Correcting for NC Artifacts Reducing false positive rate as much as possible The Achilles Heel

3 Nuclear Cardiology in 1973 and in 2012 HW Strauss, BL Zaret, ND Martin, HP Wells, Jr, and MD Flamm, Jr Noninvasive evaluation of regional myocardial perfusion with potassium 43. Technique in patients with exercise-induced transient myocardial ischemia Radiology : 85-90

4 Patient Centered Imaging and Quality Look at the global picture who is my patient? Estimate the pre test probability of disease The Achilles Heel

5 Improving Nuclear Cardiology Practice Patient Centered Imaging and Quality 1- Medical history talk to the patient Estimation of pre test probability symptoms, risk factors Interview needed to better define ideal stress protocols Needed to define which question clinician wants to answer Diagnosis? Prognosis? Culprit artery? Viability? Function? 2- Stress data Estimate functional capacity Some Diagnostic and Prognostic info Duke Score (time 5 x ST mm 4 x angina) New pre test probability before imaging Define ideal for post stress imaging 15 vs 30 vs Imaging analysis Consider info from history and stress test for image interpretation (more sensitive or specific reading consider artifacts) 4 Final report (1+2+ 3)

6 How to Recognize and to Correct for NC Artifacts Medical team should participate actively Decide best type of stress The Achilles Heel keep good quality control, systematically review image before releasing patient, verify acquisition / processing (preferably process yourself), decide when to do additional images (delayed), reacquire in prone if needed, repeat study if necessary (inadequate IV injection/sq) - Look for motion, evaluate statistics, body habitus (attenuation), history / rest ECG (prior MI? LBBB/PCM?)

7 case

8 70 yo Man HTN, Disl BMI 34 Atypical Pain Duke score -1

9 Prone Imaging

10 case

11 SPECT 99m Tc-MIBI -stress-rest No history of CAD Atypical Chest Pain Question 1 What is your interpretation? A - Silent Inferior MI B Inferior MI, LAD ischemia C Diaphragmatic attenuation D Inferior MI, Dilated LV E Not sure, need more data

12 SPECT 99m Tc-MIBI -stress-rest No history of CAD Atypical Chest Pain Question 1 What is your interpretation? A - Silent Inferior MI B Inferior MI, LAD ischemia C Diafragmatic attenuation D Dilated LV, Inferior MI E Not sure, need more data

13 Question 2 What could be helpful to differentiate a true defect and diaphragmatic attenuation in this patient? A- Prone Imaging B- Attenuation correction C Rest ECG and TMT results D- Gated SPECT E All of the above

14 Question 2 What could be helpful to differentiate a true defect and diaphragmatic attenuation in this patient? A- Prone Imaging B- Attenuation correction C Rest ECG and TMT results D- Gated SPECT E All of the above

15 Attenuation Correction using PET- CT SPECT 99m Tc-MIBI PET 82 Rb Courtesy of J. Machac-Mt Sinai, NY

16 What can we do to overcome the problem? Use LV Function data - Gated SPECT Wall motion and thickening at rest and after stress

17 Specificity (%) Gated Tc-99m SPECT improving specificity in women Tl Tc-99m Gated % Stenosis Taillefer et al JACC 1997;29:69-77

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19 % Equivocal Interpretations Prone + AC on SPECT-CT reduce number of equivocal studies Supine NC Supine NC/Prone Supine NC/AC All 5 0 Male Female Camera Time Consuming!!! Malkerneker D et al. J Nucl Cardiol 2007

20 Before and After Attenuation Correction Before After Before After Before After

21 Before and After Attenuation Correction Before After Before After Before After

22 SPECT-CT Imaging (No Attenuation Correction)

23 SPECT-CT Imaging (After Attenuation Correction)

24 Relevant questions in 2012 What information do we need to manage our patient? Is new imaging technology reducing CV mortality? Is technology translating in cost effective care? Have we already maximize extracting the information from basic techology? Vitola JV

25 Worldwide Utilization of MPI Underutilized in Many Nations High Moderate High Moderate Moderate Low Low Inexistent Limited info Vitola JV, Shaw L, Allam A, Peix A et al JNC, 2009

26 Having both information from Nuclear (physiology) and CT (Anatomy) : competition and / or cooperation?

27 Cooperation increasing both are non-invasive Roles being defined for calcium score and anatomy by CT Potential for competition: For pratical purposes CT excludes CAD (high NPV, low PPV) A negative CT implies no nuclear on follow up (including nuclear after + TMT) Acute chest pain in ER Calcium Score long term prognosis Diagnosis of CAD Secondary Prevention Plaques/Obstruction continue investigation Ischemic burden Prognosis 1-2 years Need to revascularize

28 75 yo women, no history of CAD mild antero-septal ischemia? Cortes Tomográficos-Referência Eixo Curto Eixo Longo Vertical Eixo Longo Horizontal QUANTA Diagnostico Nuclear

29 Negative CT: Mibi showed microvascular ischemia? Breast attenuation? Good Chance for Contribution and Feedback to NC

30 Negative MPI but very advanced atherosclerosis No revascularization but aggressive secondary prevention

31 Man, 57 yo, HTN, Dyslipidemia, Obese and sedentary Denies DM, Family hx, Smoking Asymptomatic on check up

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35 Calcium score 2037 LAD 962 LCX 194 RCA 881

36 Calcium score 2037 LAD 962 LCX 194 RCA 881

37 Calcium score 2037 LAD 962 LCX 194 RCA 881

38 Calcium Score Superior Compared to Framingham Score Man, 57 yo, HTN, Dyslipidemia, Obese and sedentary Denies DM, Family hx, Smoking Asymptomatic CCS 2037 Framingham Risk Score Berman DS et al. J Nucl Med 2006:47:

39 In asymptomatic patients with CCS > 400, what is the probability of a positive SPECT? A : < 10% B : 10 20% C : 20-30% D : 30-40% E : 40-50%

40 In asymptomatic patients with CCS > 400, what is the probability of a positive SPECT? A : < 10% B : 10 20% C : 20-30% D : 30-40% E : 40-50%

41 Cortes Tomográficos-Referência Eixo Curto Eixo Longo Vertical Eixo Longo Horizontal

42 Conclusions Deliver the highest possible quality NC imaging AC using SPECT CT can help Identify your value and recognize your limitations Nuclear and CT there is more room for cooperation than competition

43 Thank you