Techneitum-99m tetrofosmin single photon emission computed tomography: sensitive for diagnosing coronary artery disease, specific for diagnosing reversible perfusion defects

Background: Sensitivity for the overall detection of coronary artery diseas e Thallium-201 is approximately 85%, There is, thus, room for a more sensit ive approach. Aim: The purpose of this study was to evaluate the clinical value of visual analysis of Tc-99m tetrofosmin single photon emission computed tomography (SPECT) for the assessment of the presence, localization and extent of coro nary artery disease (CAD), Methods: Exercise myocardial perfusion imaging was prospectively performed in 85 patients. The results were compared to coronary angiographic findings which served as the gold standard, Results: Angiographic evidence for significant CAD (i.e. a luminal stenosis of 50% or more) was found in 53 patients (62%), The overall sensitivity fo r detection of CAD was 94%, specificity 78%, positive predictive value 88% and negative predictive value 89%. In addition we calculated the diagnostic value using partial or complete reversible perfusion defects instead of fi xed or reversible perfusion defects; a lower sensitivity (64%) and a higher specificity (97%) were found. For the detection of multivessel disease ins tead of single or no vessel disease the sensitivity and specificity were bo th 68%, The left anterior descending coronary artery, the right coronary ar tery and the left circumflex artery showed a sensitivity of 74%, 89% and 44 % and a specificity of 70%, 64% and 88%, re-spectively. Conclusion: This study demonstrates that Tc-99m tetrofosmin SPECT is quite sensitive for the overall detection of CAD, and specific for the detection of reversible perfusion defects.