title: A normal stress SPECT scan is an effective gatekeeper for coronary angiography.
abstract: BACKGROUND
  The effectiveness of stress single photon emission computed tomography (SPECT) as a gatekeeper for coronary angiography has not been extensively investigated. The characteristics of patients referred for early angiography after a normal stress SPECT study have not been described.
  
  
  RESULTS
  Over a 10-year period, 14,273 patients without documented coronary artery disease (CAD) underwent stress SPECT. Images were abnormal in 47% and normal in 53%. The overall survival rate at 15 years was 55% for patients with abnormal images versus 71% for those with normal images (P < .001). Early coronary angiography (< or =3 months) was performed in only 97 patients (1.3%) with normal SPECT studies versus 1,756 patients (26%) with abnormal SPECT studies (P < .001). Most patients with normal SPECT studies referred for early angiography (85%) had clinical, exercise, or scintigraphic findings worrisome for CAD. Two thirds of these highly selected patients with normal SPECT studies who underwent angiography did not have significant CAD; the remaining one third had primarily 1- and 2-vessel CAD.
  
  
  CONCLUSIONS
  Stress SPECT is an effective gatekeeper for coronary angiography. The annual overall mortality rate for patients with normal images was 1.9%. Only 1.3% of patients with normal images were referred for early angiography.
authors: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minn 55905, USA. miller.todd@mayo.edu
authors: Todd D
authors: TD
authors: Miller
authors: David O
authors: DO
authors: Hodge
authors: James J
authors: JJ
authors: Milavetz
authors: Raymond J
authors: RJ
authors: Gibbons
mesh_terms: D017023:Coronary Angiography / Q000706:statistics & numerical data*; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000401:mortality*; D005080:Exercise Test / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012017:Referral and Consultation / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D015899:Tomography, Emission-Computed, Single-Photon / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology