title: Usefulness of exercise test and myocardial perfusion-gated single photon emission computed tomography to improve the prediction of major events.
abstract: BACKGROUND
  The incremental prognostic value of myocardial perfusion-gated single photon emission computed tomography (MPGS) compared with exercise test has not yet been properly evaluated.
  
  
  RESULTS
  Five thousand six hundred seventy-two consecutive patients with known or suspected coronary disease undergoing exercise MPGS between 1997 and 2007 were included. Three-year predictive models for total death and death from cardiovascular causes or acute myocardial infarction (ie, major cardiovascular events [MCE]) were built using Cox-regression modeling, including only the clinical information. Then the exercise and MPGS information was sequentially added. The added discriminative ability of exercise test information and MPGS was assessed by net reclassification improvement and integrated discrimination improvement. The increase in predictive ability of exercise information for death and MCE was high as assessed by net reclassification improvement (0.199 and 0.263) and integrated discrimination improvement (0.042 and 0.021). The only variable of MPGS associated with total death was ejection fraction (hazard ratio, 0.84; 95% confidence interval, 0.79-0.89; P<0.001). Global stress ischemic score emerged as an additional variable associated with MCE (hazard ratio, 1.07; 95% confidence interval, 1.02-1.12; P=0.007). Adding MPGS information barely improved the prognostic value for total death (net reclassification improvement, 0.017; integrated discrimination improvement, 0.013), but it increased for MCE (net reclassification improvement, 0.122; integrated discrimination improvement, 0.033).
  
  
  CONCLUSIONS
  Adding MPGS information to exercise information does not improve prediction of total death, although it allows a more accurate prediction of MCE.
authors.affiliation: Department of Cardiology, Hospital Universitari Vall d'Hebron, Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Candell-Riera
authors.forename: Ignacio
authors.initials: I
authors.lastname: Ferreira-González
authors.forename: Josep R
authors.initials: JR
authors.lastname: Marsal
authors.forename: Santiago
authors.initials: S
authors.lastname: Aguadé-Bruix
authors.forename: Gemma
authors.initials: G
authors.lastname: Cuberas-Borrós
authors.forename: Paula
authors.initials: P
authors.lastname: Pujol
authors.forename: Guillermo
authors.initials: G
authors.lastname: Romero-Farina
authors.forename: María
authors.initials: M
authors.lastname: Nazarena-Pizzi
authors.forename: Gustavo
authors.initials: G
authors.lastname: de León
authors.forename: Joan
authors.initials: J
authors.lastname: Castell-Conesa
authors.forename: David
authors.initials: D
authors.lastname: García-Dorado
mesh_terms: D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D016002:Discriminant Analysis; D018450:Disease Progression; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000209:etiology / Q000401:mortality; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors
keywords: cardiac-gated SPECT imaging; coronary disease; perfusion; prognosis