Is There a Role for Nuclear Cardiology in the Era of Cardiac CT? E. Gordon DePuey, M.D. Select the Appropriate Test to Meet the Patient Need

Transcription

1 Is There a Role for Nuclear Cardiology in the Era of Cardiac CT? E. Gordon DePuey, M.D. Clinical Professor of Radiology Icahn School of Medicine at Mt. Sinai Director of Nuclear Medicine Mt. Sinai St. Luke s and Roosevelt Hospitals New York, NY Select the Appropriate Test to Meet the Patient Need Prevention Diagnosis Management of known disease Cost containment 1

2 Cardiac CT: Anatomy Strengths Rapid, easily performed, utilizes standard x-ray equipment 3D high spatial resolution Non-contrast CAC: proven role for prevention Contrast CTCA High sensitivity and specificity for CAD Potential for comprehensive cardiac assessment Function, perfusion, infarct, plaque Strong prognostic value Weaknesses Densely calcified plaque non-diagnostic Low HR (<65 bpm) and regular rhythm required Radiation, iodinated contrast Myocardial Perfusion SPECT/PET: Physiology Strengths High technical success rate Objective measurement of perfusion and function Documented for risk-stratification/management MBFR with PET and advanced SPECT Promising new tracer, F-18 flurdiripaz, in Phase III Limitations No detection of early atherosclerosis/unstable plaque Frequently underestimates extent of ischemic CAD/ balanced ischemia 2

3 Event Rate Per Year (Percentage) 3/29/2015 Value of Stress MPI in the General Population: Prognosis: MPI Scan Severity Predicts Outcome Cardiac death MI * n=2946 Normal n=884 Mildly Abnormal n=455 Moderately n=898 Severly Abnormal Abnormal Scan Result Hachamovitch R, et al. Circulation. 1998;97: Downstream Testing Hachamovitch at al. J Am Coll Cardiol 2012;59:

4 Relationship between Stenosis Severity by CCTA and Ischemia on SPECT MPI Tamarappoo et al, J Nucl Card 2010;17: CAC/CTCA May Overestimate Stenosis 4

5 SAGMAN 67M 10/2/07 # Atypical chest pain; hypertension; cholesterol Medications: Statin, beta blocker LM/LAD/LCX LAD RCA Courtesy Dan Berman, M.D., CSMC Courtesy Dan Berman, M.D., CSMC 5

6 MPI May Underestimate Stenosis LIBANN 58 F 2/26/08 # Stress Rb Rest Rb Stress Rb Rest Rb Stress Rb Rest Rb Stress Rb Rest Rb Courtesy Dan Berman, M.D., CSMC 6

7 LIBANN 58 F 2/26/08 # Calcium Score 698 (99th percentile) Courtesy Dan Berman, M.D., CSMC Normal Perfusion SPECT MAYBE NOT! Scan Findings Suggestive of Balanced Ischemia RV uptake with exercise TID with normal or mildly abnormal perfusion Drop in LVEF (post-stress versus rest) Exercise/Pharmacologic Stress Parameters Suggesting Ischemia Hypotensive response to exercise Chronotropic incompetence 7

8 MPI Does Not Identify High Risk Plaque Without Significant Stenosis Gupta, G. Proc Bayl Univ Med Cent October;21(4):

9 Advances in SPECT and PET Instrumentation and Radiopharmaceuticals: New and on the Horizon 9

10 MBF Assessment With Rb-82 PET LV GFADS LV VOI RV GFADS RV VOI MYO GFADS MYO VOI seconds El Fakhri, Sitek, et al. J. Nucl. Med 2005, Brigham & Women s H Dynamic D-SPECT Acquisition Right and Left Ventricular and Myocardial Time-activity Curves and Corresponding 6-second Mid-Ventricular Short-axis Tomograms 20,000 18,000 RV Input LV Input Myocardium 16,000 14,000 12,000 (Bq/mL) 10,000 8,000 6,000 4,000 2, Time (S) Courtesy Dr. Simona Ben-Haim, Chaim Sheba Medical Center, Tel Hashomer, Israel 10

11 Dynamic Protocol to Assess Coronary Flow Reserve Case Example MIBI STR MIBI RST Patient 2: Male - 69 years old Previous inferior MI Pre-operative assessment for total knee replacement STR RST STRESS EF = 38% Courtesy of University college of London Simona Ben-Haim MD, DSc Partial thickness inferior wall infarct, extending to apex and basal lateral wall with superimposed ischemia D-SPECT, Spectrum Dynamics Dynamic Protocol to Assess Coronary Flow Reserve Case Example Time Activity curves (TAC) Coronary flow reserve index (CFRI) STRESS TIME-ACTIVITY CURVES COUNTS RV bolus LV bolus LV tissue TIME REST TIME-ACTIVITY CURVES COUNTS RV bolus LV bolus LV tissue TIME low CFRI values (estimated lower limit ~1.2) High risk of triple vessel disease D-SPECT, Spectrum Dynamics 11

12 J Nucl Cardiol 2011;18: J Nucl Cardiol 2011;18:

13 Epicardial vessels Small vessels 3/29/2015 Physiologic Assessment of the Coronary Circulation FFR CFR ASNC 2014 PET Summit, Courtesy M. DiCarli, M.D 13

14 Conclusions: SPECT and PET MPI High technical success rate Proven excellent prognostic value Low downstream costs Lower radiation dose (2-7 msv) with Stress-only protocol New SPECT hardware/software PET Important new advancements Myocardial blood flow reserve F-18 flurdiripaz Limitations: balanced ischemia; high risk plaque 14

15 Thank You 15