title: Multislice computed tomography in the exclusion of coronary artery disease in patients with presurgical valve disease.
abstract: BACKGROUND
  Multislice computed tomography (MSCT) has shown high negative predictive value in ruling out obstructive coronary artery disease. Preliminary studies in patients with valvular heart disease (VHD) have demonstrated the potential of MSCT angiography (CTA) in such patients, precluding need for invasive angiography (XA). However, larger prospectively designed studies, including patients with atrial fibrillation and incorporating dose reduction algorithms, are needed.
  
  
  RESULTS
  To evaluate the clinical utility of 64-slice CT in the preoperative assessment in patients with VHD, we prospectively studied 452 consecutive patients undergoing routine cardiac catheterization for eligibility. Two hundred thirty-seven patients underwent both MSCT and XA. Segment-based, vessel-based, and patient-based agreement between CTA and XA was estimated assuming that "nonevaluable" segments were positive for significant coronary stenosis. In a patient-based analysis, sensitivity, specificity, positive predictive value, and negative predictive values of CTA were 95%, 89%, 66%, and 99%, respectively; in vessel-based analysis, 90%, 92%, 48%, and 99%, respectively; and in segment-based analysis, 89%, 97%, 38%, and 100%, respectively. No significant differences were found between patients with or without atrial fibrillation. A CAC value of 390 was the best cutoff for the identification of patients with positive or inconclusive CTA (which would not be exempted from XA in the clinical setting).
  
  
  CONCLUSIONS
  In the preoperative assessment of patients with predominant VHD, the diagnostic accuracy of 64-slice CTA for ruling out the presence of significant coronary artery disease is very good even when including patients with irregular heart rhythm. Using this approach, CAC quantification before CTA can be successfully used to identify patients who should be referred directly to XA, sparing unnecessary exposure to radiation.
authors.affiliation: Cardiology Department, Centro Hospitalar de Gaia/Espinho, Vila Nova de Gaia, Portugal. bettencourt.n@gmail.com
authors.forename: Nuno
authors.initials: N
authors.lastname: Bettencourt
authors.forename: João
authors.initials: J
authors.lastname: Rocha
authors.forename: Mónica
authors.initials: M
authors.lastname: Carvalho
authors.forename: Daniel
authors.initials: D
authors.lastname: Leite
authors.forename: Andre Michael
authors.initials: AM
authors.lastname: Toschke
authors.forename: Bruno
authors.initials: B
authors.lastname: Melica
authors.forename: Lino
authors.initials: L
authors.lastname: Santos
authors.forename: Alberto
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Manuel
authors.initials: M
authors.lastname: Gonçalves
authors.forename: Pedro
authors.initials: P
authors.lastname: Braga
authors.forename: Madalena
authors.initials: M
authors.lastname: Teixeira
authors.forename: Lino
authors.initials: L
authors.lastname: Simões
authors.forename: Sanjay
authors.initials: S
authors.lastname: Rajagopalan
authors.forename: Vasco
authors.initials: V
authors.lastname: Gama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures; D017023:Coronary Angiography / Q000009:adverse effects / Q000379:methods*; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging*; D005188:False Negative Reactions; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011446:Prospective Studies; D012372:ROC Curve; D011829:Radiation Dosage; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000009:adverse effects; D019564:Unnecessary Procedures