myocardial perfusion imaging

• thallium (Tl) 201
  • acts as potassium analog
  • dose 3.0 - 5.0 mCi at peak exercise
  • 4% of injected dose --> myocardium

  • imaging: "exercise" (5-10 min), "redistribution" (3-4 hrs)
  • views: anterior, LAO 45', left lateral

  • interpretation:
    • normal
    • reversible abnl ==> exercise-induced ischemia
    • nonreversible abnl ==> prior MI
    • reverse redistribution ==> normal areas wash out faster
    • lung activity ==> LV failure during exercise

• Tc99m sestamibi
  • myocardial uptake proportional to perfusion
  • no redistribution
  • dose 25mCi

  • imaging: optimal at 1hr but maybe satisfactory out to three hours

• dipyridamole test
• nuclear cardiology

© 2002, C.E. Kahn, Jr.
2002-04-18