Prognostic Value of Normal Exercise and Adenosine 99mTc-Tetrofosmin SPECT Imaging: Results from the Multicenter Registry of 4,728 Patients

Event rates associated with a normal or low-risk myocardial perfusion SPECT imaging study have been shown by numerous investigators to be associated with 1%/y of follow-up. Thus, the aim of this study was to evaluate the prognostic value of a normal 99mTc-tetrofosmin study in a geographically diverse reg-istry of patients undergoing stress myocardial perfusion SPECT. A total of 4,728 consecutively tested patients who underwent stress 99mTc-tetrofosmin SPECT at 5 U.S. hospitals were in-cluded in this series. Methods: Patients were monitored for the occurrence of major cardiac events and hospitalizations. Uni-form methods of data collection and standardized epidemio-logic methods for follow-up were used at all centers. We used a risk-adjusted, Cox proportional hazards model to assess time to cardiac death. Results: Of the 4,728 patients, one third under-went adenosine stress SPECT and two thirds underwent tread