SPECT MPI

• Framingham Risk Stratification:
  • High Risk >3%:
    • Resting LVEF <35%
    • High risk treadmill score ≤-11
    • Exercise LVEF <35%
    • Stress induced large perfusion defect
    • Multiple, moderate-sized perfusion defects
    • Large, fixed perfusion defect with LV dilation or increased lung uptake
    • more than 2 segments of wall motion abnormalities on echo at low dobutamine does or low HR <102
    • Stress echo evidence of extensive ischemia
  • Intermediate Risk (1-3%):
    • Mild/moderate resting LV dysfunction (LVEF 35-49%)
    • Duke Treadmill -11 to 5
    • Stress induced moderate perfusion defect
    • ≤2 segments of wall motion abnormalities on echo at high dobutamine does or low HR <102
  • Low Risk (<1%)
    • Low risk Duke treadmill score ≥5
    • Normal or small defect at rest or with stress
    • Normal stress echo wall motion or no change of limited resting wall motion abnormalities during stress

Single Photon Emission Computed Tomography (SPECT) Myocardial Perfusion Imaging Guidelines¶

• Instrumentation, Acquisition, Processing, and Interpretation
• Stress, protocols, and tracers
• Quality metrics

LOW-RISK STRESS FINDINGS (associated with a cardiac mortality of less than 1% per year)¶

• 1. Low risk treadmill score (score ≥ 5)
• 1. Normal or small myocardial perfusion defect at rest or with stress
• 1. Normal stress echocardiographic wall motion or no change of limited resting wall motion abnormalities during stress

INTERMEDIATE-RISK STRESS FINDINGS (associated with a 1-3% per year cardiac mortality)¶

• 1. Mild/moderate resting left ventricular dysfunction (LVEF 35-49%)
• 1. Intermediate risk treadmill score (-11 score to < 5)
• 1. Stress-induced moderate perfusion defect without LV dilation or increased lung intake (thallium-201)

HIGH-RISK STRESS FINDINGS (associated with a >3% per year cardiac mortality)¶

• 1. Severe resting left ventricular dysfunction (LVEF < 35%)
• 1. High-risk treadmill score (score ≤ -11)
• 1. Severe exercise left ventricular dysfunction (exercise LVEF < 35%)
• 1. Stress-induced large perfusion defect (particularly if anterior)
• 1. Stress-induced multiple perfusion defects of moderate size.
• 1. Large, fixed perfusion defect with LV dilation or increased lung uptake (Thallium-201)
• 1. Stress-induced moderate perfusion defect with LV dilation or increased lung uptake (thallium-201)

Balanced Ischemia¶

• High risk features on Exercise testing
  • Coronary blood low is equally or nearly equally impaired
  • ST depression in multiple leads during peak stress but no evidence of ischemia on radionuclide MPI