EVALUATION OF CORONARY-ARTERY DISEASE USING TECHNETIUM-99M-SESTAMIBI FIRST-PASS AND PERFUSION IMAGING WITH DIPYRIDAMOLE INFUSION

The aims of this study were: (1) to test whether first-pass radionucli de angiocardiography (FPRNA) adds useful information to perfusion scin tigraphy; and (2) to assess the relative accuracy of perfusion and fun ctional imaging in combination with dipyridamole for the evaluation of CAD. Methods: Thirty patients with angiographically proven CAD (17 wi th prior infarction) were studied on separate days at rest and with di pyridamole infusion (0.7 mg/kg over 4 min). Tomographic images were ev aluated using an uptake score. Dipyridamole FPRNA was considered posit ive in case of stress-induced wall motion abnormality or ejection frac tion decrease. Results: The CAD detection rate of perfusion imaging wa s 100%, while that of FPRNA was 70% using wall motion criteria, 63% us ing ejection fraction response and 77% considering any abnormality. Fo r CAD localization, perfusion imaging showed 76% sensitivity, 96% spec ificity and 82% accuracy. FPRNA results were 50%, 100% and 60%, respec tively. Perfusion imaging was significantly superior to FPRNA also exc luding from the analysis the infarct-related vessels. FPRNA did not id entify multivessel CAD, which was correctly detected by perfusion imag ing in most cases. Both techniques were more sensitive in case of grea ter than or equal to 90% stenosis, but the difference was more remarka ble for FPRNA (sensitivity 65% versus 14%, p < 0.0005). Conclusions: D ipyridamole FPRNA did not add noteworthy clinical information to perfu sion imaging regarding CAD detection and evaluation of disease extent. The main contribution of a positive FPRNA was its relation with coron ary obstruction severity. These results confirm the superiority of per fusion over functional imaging in combination with coronary vasodilato rs.