title: Diagnostic value of ischemia severity at myocardial perfusion imaging in elderly persons with suspected coronary disease.
abstract: OBJECTIVE
  Myocardial perfusion and ischemia scores obtained from myocardial perfusion scintigraphy (MPS) have strong independent prognostic value in elderly individuals without known coronary artery disease (CAD). Herein we aimed to assess their independent diagnostic value and accuracy for CAD while considering different thresholds of myocardial ischemia.
  
  
  METHODS
  We estimated the summed rest score (SRS), summed stress score (SSS) and summed difference score (SDS) in 322 elderly individuals (mean age 72 ± 7 years, 68% men) who underwent coronary angiography following an MPS. Abnormal perfusion at stress was defined as an SSS greater than 3, and ischemia as an SDS of at least 2, and further categorized as mild (2-4), moderate (5-7) or severe (>7). Multivariate logistic regressions were used to establish the independent diagnostic value and accuracy of MPS parameters.
  
  
  RESULTS
  CAD was diagnosed in 182 individuals (56%). In multivariate analysis accounting for clinical variables associated with CAD including the Framingham risk score, both SRS [odds ratio (OR) 1.09, 95% confidence interval (CI) 1.01-1.18, P = 0.03] and SSS (OR 1.10, 95% CI 1.04-1.16, P = 0.0006) and SDS (OR 1.12, 95% CI 1.04-1.21, P = 0.003) were independently associated with CAD. An SSS greater than 3 was also independently associated with CAD (OR 2.51, 95% CI 1.43-4.39, P = 0.0013), whereas an SDS of 2 or greater was not (OR 1.62, 95% CI 0.89-2.93, P = 0.12), but only when at least 5 (OR 2.31, 95% CI 1.32-4.03, P = 0.003). The probability of CAD was proportional to the amount of myocardial ischemia in those with an SSS greater than 3, and lower and comparable in those with an SSS of at least 3 or an SSS greater than 3 with SDS of 1 or less (P = 0.19). Increasing the threshold of myocardial ischemia determined a decrease in sensitivity and increase in specificity of MPS for both diagnosis and severity of CAD.
  
  
  CONCLUSIONS
  We established the diagnostic value and accuracy of continuous scores and thresholds of abnormal myocardial perfusion and ischemia previously validated in prognostic studies. Their more widespread use could potentially improve the diagnostic yield of coronary angiography in elderly individuals with suspected CAD.
authors.affiliation: aCardiovascular Unit, Department of Internal Medicine, University of Genova, Genova, Italy bLongitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, Maryland, USA cDepartment of Psychiatry, VU University Medical Center/GGZ in Geest, Amsterdam, The Netherlands dNuclear Medicine, Department of Health Science, University of Genova, Genova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Canepa
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Bezante
authors.forename: Pierfilippo
authors.initials: P
authors.lastname: Vianello
authors.forename: Pietro
authors.initials: P
authors.lastname: Ameri
authors.forename: Yuri
authors.initials: Y
authors.lastname: Milaneschi
authors.forename: Milena
authors.initials: M
authors.lastname: Aste
authors.forename: Francesca
authors.initials: F
authors.lastname: Cavalla
authors.forename: Matteo
authors.initials: M
authors.lastname: Bauckneht
authors.forename: Cecilia
authors.initials: C
authors.lastname: Marini
authors.forename: Manrico
authors.initials: M
authors.lastname: Balbi
authors.forename: Claudio
authors.initials: C
authors.lastname: Brunelli
authors.forename: Gianmario
authors.initials: G
authors.lastname: Sambuceti
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology; D004176:Dipyridamole / Q000008:administration & dosage*; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D007558:Italy; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D055414:Myocardial Perfusion Imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D014665:Vasodilator Agents; D004176:Dipyridamole