Impact of clinical data and interhospital agreement in interpretation of myocardial perfusion (SPET)

Introduction and objectives. The aim of this study is to analyze the impact of clinical data and the interhospitalary agreement in the interpretation of myocardial perfusion single photon emission tomography (SPET) images and polar mapping. Methods. 150 patients from 5 hospitals were studied. Each center contribute d with tomographic images and polar maps of (99)mTc-tetrofosmin exercise SP ET and clinical reports of 30 patients. Thus, 300 images (150 of tomographi c images and 150 of polar maps) were interpreted by each center without kno wledge of clinical data of the patient ("blinded" report). Results. 90 (60%) out of 150 patients had a coronary stenosis greater than or equal to 50%. Sensitivity and specificity of "non blinded" report were 9 1% and 86%, respectively. Sensitivity determined by majoritary decision (th ree or more centers) was 82% for tomographic images and 83% for polar maps (p = 0.002 and p = 0.03, respectively, regarding he "non blinded" report). Specificity was 88% for tomographic images and 79% for polar map (p = 0.05 with respect to tomographic images). Interhospitalary agreement was good no t only for tomographic images (kappa: 0.625) but for polar maps (kappa: 0.7 ) as well, Conclusions. Sensitivity of clinical or "non blinded" report of myocardial perfusion SPET is significantly higher than the "blinded" report. Specifici ty of the "blinded" report of polar mapping is lower than that of tomograph ic images. A good interhospitalary agreement in interpretation of both type s of images was observed.