title: Combined low dose dipyridamole-dobutamine stress echocardiography to identify myocardial viability.
abstract: OBJECTIVE
  We sought to evaluate the effects of combined administration of infra-low dose dipyridamole and low dose dobutamine on assessment of myocardial viability.
  
  
  BACKGROUND
  Low dose pharmacologic stress echocardiography with either dobutamine or dipyridamole infusion has been proposed for the recognition of myocardial viability.
  
  
  METHODS
  Thirty-four patients with rest wall motion dyssynergy by two-dimensional echocardiography and with angiographically proved coronary artery disease underwent in combination with two-dimensional echocardiographic monitoring: 1) low dose (5 to 10 microgram/kg per min over 3 min) dobutamine infusion; 2) infra-low dose (0.28 mg/kg over 4 min) dipyridamole infusion; 3) combination of infra-low dose dipyridamole infusion immediately followed by low dose dobutamine infusion (combined dipyridamole-dobutamine).
  
  
  RESULTS
  Follow-up rest echocardiography was available in 30 patients. After revascularization, 82 segments showed a contractile improvement of > or = 1 grade, whereas 63 segments remained unchanged. The sensitivity of dobutamine, dipyridamole and combined dipyridamole-dobutamine for predicting recovery was 72% (95% confidence interval [CI] 60.9% to 81.3%), 67% (CI 55.8% to 77%) and 94% (CI 86.3% to 97.9%), respectively. The specificity of dipyridamole, dobutamine and combined dipyridamole-dobutamine was 95% (CI 86.7% to 99%), 92% (CI 82.4% to 97.3%) and 89% (CI 78.4% to 95.4%), respectively. The accuracy of the dobutamine, dipyridamole and combined dipyridamole-dobutamine test was 80%, 79% and 92%, respectively (combined dipyridamole-dobutamine vs. dobutamine, p < 0.05; combined dipyridamole-dobutamine vs. dipyridamole, p < 0.01).
  
  
  CONCLUSIONS
  Infra-low dose dipyridamole added to low dose dobutamine recruits an inotropic reserve in asynergic segments that were nonresponders after either dobutamine or dipyridamole alone and destined to recover after revascularization.
authors.affiliation: Consiglio Nazionale della Richerche, Institute of Clinical Physiology, Pisa, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Picano
authors.forename: M
authors.initials: M
authors.lastname: Ostojic
authors.forename: A
authors.initials: A
authors.lastname: Varga
authors.forename: R
authors.initials: R
authors.lastname: Sicari
authors.forename: A
authors.initials: A
authors.lastname: Djordjevic-Dikic
authors.forename: I
authors.initials: I
authors.lastname: Nedeljkovic
authors.forename: M
authors.initials: M
authors.lastname: Torres
mesh_terms: D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004176:Dipyridamole / Q000008:administration & dosage; D004280:Dobutamine / Q000008:administration & dosage; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014022:Tissue Survival
chemical_list: D004280:Dobutamine; D004176:Dipyridamole