Enhanced detection of reversible perfusion defects by Tc-99m sestamibi compared to Tc-99m tetrofosmin during vasodilator stress SPECT imaging in mild-to-moderate coronary artery disease

J Am Coll Cardiol. 2001 Feb;37(2):458-62. doi: 10.1016/s0735-1097(00)01148-7.


Objectives: We prospectively compared dipyridamole single-photon emission computed tomography (SPECT) imaging with Tc-99m sestamibi and Tc-99m tetrofosmin for the detection of reversible perfusion defects in patients with mild-to-moderate coronary artery disease.

Background: Tc-99m tetrofosmin has a lower first-pass myocardial extraction fraction compared to Tc-99m sestamibi and thus could underestimate mild perfusion defects.

Methods: Eighty-one patients with 50% to 90% stenosis in one or two major epicardial vessels without previous myocardial infarction, and seven with <5% probability of coronary artery disease underwent dipyridamole SPECT imaging with both agents. The SPECT data were analyzed quantitatively.

Results: Tc-99m sestamibi detected reversible perfusion defects in a greater number of segments (total 363 and 285, p < 0.001, and mean +/- SD, 2.2 +/- 3.0 and 1.8 +/- 2.5 per patient, p = 0.008, for Tc-99m sestamibi and Tc-99m tetrofosmin, respectively), demonstrated a larger extent of perfusion defect (mean +/- SD, 15.8% +/- 12.3% and 12.0% +/- 11.4%, p < 0.03, for Tc-99m sestamibi and Tc-99m tetrofosmin, respectively) and more often correctly identified patients with disease in more than one coronary artery (p = 0.02). There was better defect contrast with Tc-99m sestamibi (defect/normal wall count ratios were 0.60 +/- 0.15 vs. 0.73 +/- 0.14 for Tc-99m sestamibi and Tc99m tetrofosmin, respectively, p = 0.01, for reversible defects seen in identical segments with both agents; and 0.73 +/- 0.16 vs 0.79 +/- 0.17, respectively, p <0.01, for reversible defects detected with either agent alone). There was no significant difference in diagnostic sensitivity or image quality.

Conclusions: These differences between two commonly used tracers may have significant diagnostic and prognostic implications.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Coronary Circulation / drug effects*
  • Coronary Disease / diagnostic imaging*
  • Dipyridamole*
  • Exercise Test
  • Female
  • Humans
  • Male
  • Middle Aged
  • Organophosphorus Compounds
  • Organotechnetium Compounds
  • Sensitivity and Specificity
  • Technetium Tc 99m Sestamibi*
  • Tomography, Emission-Computed, Single-Photon*
  • Vasodilator Agents*


  • Organophosphorus Compounds
  • Organotechnetium Compounds
  • Vasodilator Agents
  • technetium tc-99m tetrofosmin
  • Dipyridamole
  • Technetium Tc 99m Sestamibi