title: Dipyridamole stress echocardiography vs dipyridamole sestamibi scintigraphy for diagnosing coronary artery disease in left bundle-branch block.
abstract: OBJECTIVE
  To evaluate dipyridamole stress echocardiography (DSE) for predicting coronary artery diseases (CADs) in patients with complete left bundle-branch block (LBBB).
  
  
  METHODS
  Comparison of DSE and dipyridamole sestamibi myocardial perfusion scintigraphy (sestamibi).
  
  
  METHODS
  Tertiary-care cardiac referral center.
  
  
  METHODS
  Fifty-four consecutive patients (26 men; mean [+/- SD] age, 59 +/- 7 years) with complete LBBB (14 patients with left ventricular [LV] dilatation) and intermediate probability of CAD.
  
  
  METHODS
  Simultaneous single photon emission CT scan (20 mCi technetium Tc 99m stress/rest sestamibi) and echocardiography (second harmonic imaging) during a two-step (0.56 to 0.84 mg/kg) dipyridamole infusion protocol. Two sestamibi readings were performed. The first reading considered only those studies with reversible defects (sestamibi-1) to be positive. The second reading considered those studies with any defect (sestamibi-2) to be positive. CAD was defined as a >or= 50% reduction in diameter in at least one major vessel seen on coronary angiography.
  
  
  RESULTS
  CAD was present in 17 patients (31.5%). The global predictive accuracy for CAD was significantly higher for DSE (87.0%) and sestamibi-1 (79.6%) than for sestamibi-2 (57.4%) [p < 0.01 vs DSE; p < 0.05 vs sestamibi-1]. No significant differences in sensitivity were present, but specificity was significantly higher for DSE (94.6%) and sestamibi-1 (81.1%) than for sestamibi-2 (43.2%; p < 0.01 vs both the other two tests). Of 14 patients with LV dilatation, 26.8% were falsely positive for CAD (in some cases for posterior defects) as determined by sestamibi-1 and 64.3% were falsely positive for CAD by sestamibi-2 vs none by DSE.
  
  
  CONCLUSIONS
  DSE is at least as accurate as dipyridamole sestamibi scintigraphy for predicting CAD in patients with complete LBBB and tends to be more specific in those patients with underlying LV dilatation.
authors.affiliation: Department of Cardiology, Casa Sollievo della Sofferenza Hospital, IRCCS, San Giovanni Rotondo, Roma, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Vigna
authors.forename: M
authors.initials: M
authors.lastname: Stanislao
authors.forename: V
authors.initials: V
authors.lastname: De Rito
authors.forename: A
authors.initials: A
authors.lastname: Russo
authors.forename: R
authors.initials: R
authors.lastname: Natali
authors.forename: T
authors.initials: T
authors.lastname: Santoro
authors.forename: F
authors.initials: F
authors.lastname: Loperfido
mesh_terms: D002037:Bundle-Branch Block / Q000150:complications*; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004176:Dipyridamole; D025401:Echocardiography, Stress; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D004176:Dipyridamole; D017256:Technetium Tc 99m Sestamibi