title: Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block.
abstract: BACKGROUND
  Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB).
  
  
  OBJECTIVE
  To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy.
  
  
  METHODS
  Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee.
  
  
  RESULTS
  The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001).
  
  
  CONCLUSIONS
  The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB.
authors.affiliation: Departamento de Tomografia e Ressonância Cardiovascular, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Estêvan Vieira
authors.initials: EV
authors.lastname: Cabeda
authors.affiliation: Departamento de Medicina Nuclear, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Andréa Maria Gomes
authors.initials: AM
authors.lastname: Falcão
authors.affiliation: Departamento de Medicina Nuclear, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: José
authors.initials: J
authors.lastname: Soares
authors.affiliation: Departamento de Tomografia e Ressonância Cardiovascular, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Rochitte
authors.affiliation: Departamento de Tomografia e Ressonância Cardiovascular, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: César Higa
authors.initials: CH
authors.lastname: Nomura
authors.affiliation: Departamento de Tomografia e Ressonância Cardiovascular, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Luiz Francisco Rodrigues
authors.initials: LF
authors.lastname: Ávila
authors.affiliation: Departamento de Tomografia e Ressonância Cardiovascular, Instituto do Coração, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: José Rodrigues
authors.initials: JR
authors.lastname: Parga
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging*; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D004176:Dipyridamole; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000295:instrumentation; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011446:Prospective Studies; D000069079:Radiation Exposure; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D004176:Dipyridamole