Combined assessment of regional perfusion and wall motion in patients with coronary artery disease with technetium 99m tetrofosmin

Background

Technetium 99m tetrofosmin is a new^99mTc-labeled myocardial perfusion agent that can be labeled easily and provides excellent myocardial perfusion images. In addition, bolus administration of the tracer allows first-pass radionuclide ventriculography.

Methods and Results

This study examined the diagnostic value of combined assessment of regional perfusion by tetrofosmin tomography and wall motion by first-pass radionuclide ventriculography both at rest and during stress in 24 patients suspected of having coronary artery disease. All patients underwent stress-rest tetrofosmin tomography, stress-delayed thallium 201 tomography, and coronary angiography. Stress tetrofosmin tomography showed abnormal perfusion in all 23 patients with angiographic evidence of coronary artery disease, whereas stress²⁰¹Tl tomography showed abnormal perfusion in 22 of the 23 patients. For detection of significant (≥50% diameter stenosis) stenotic coronary arteries, the two perfusion studies showed similar sensitivities (62% with²⁰¹Tl and 69% with tetrofosmin) and specificities (88% and 100%, respectively). When analysis of regional wall motion was combined with perfusion study, a slightly higher sensitivity was obtained (77%), with similar specificity. The regional wall motion score was concordant with the regional perfusion score in only 42% of the segments at rest and 50% during exercise.

Conclusions

These results suggest that stress tetrofosmin perfusion tomography and stress²⁰¹Tl tomography provided similar diagnostic accuracy for detection of coronary artery disease. The combined assessment of perfusion and function that is feasible with tetrofosmin may enhance diagnostic accuracy in patients with coronary artery disease.