title: Feasibility of semi-quantitative assessment of left ventricular contractile reserve in dilated cardiomyopathy.
abstract: BACKGROUND
  We and others have shown previously that left ventricular (LV) contractile reserve assessed quantitatively by high-dose dobutamine stress-echocardiography (DSE) has prognostic implications in patients with dilated cardiomyopathy.
  
  
  OBJECTIVE
  To assess the feasibility of semi-quantitative assessment of LV contractile reserve by differently skilled operators in patients with dilated cardiomyopathy.
  
  
  METHODS
  High-dose DSE was performed in 63 consecutive patients, mean age 50 ± 10 years and ejection fraction (EF) 19 ± 8%. LVEF was calculated 1) using Simpson's biplane formula, and 2) semi-quantitatively (5% increments) by novice and experienced echocardiographers, and by a DSE expert. Patients were considered to have preserved LV contractile reserve if LVEF dobutamine-induced change was ≥5%.
  
  
  RESULTS
  Twenty-seven (45.8%) patients died during the 5-year follow-up. The feasibility of the assessment was 89%, 94%, and 98% for novice and experienced readers and DSE expert, respectively. Kaplan-Meier analysis showed that LV contractile reserve assessed semi-quantitatively by DSE expert and experienced reader achieved the best prognostic separation (log rank 19.63 and 18.99, respectively, p < 0.001 for both), followed by quantitative assessment (log rank 9.76, p = 0.0018) and assessment by novice reader (log rank 8.76, p = 0.012). Areas under the curves were similar for quantitative and semi-quantitative assessment of LV contractile reserve.
  
  
  CONCLUSIONS
  Our data indicate that semi-quantitative assessment of LV contractile reserve is feasible by differently skilled operators.
authors.affiliation: Dr Aleksandar D. Popovic Cardiovascular Research Center, Dedinje Cardiovascular Institute and Belgrade University Medical School, Belgrade, Serbia.
authors.forename: Petar
authors.initials: P
authors.lastname: Otasevic
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Tasic
authors.forename: Radoslav
authors.initials: R
authors.lastname: Vidakovic
authors.forename: Srdjan
authors.initials: S
authors.lastname: Boskovic
authors.forename: Djordje
authors.initials: D
authors.lastname: Radak
authors.forename: Bosko
authors.initials: B
authors.lastname: Djukanovic
authors.forename: Lazar
authors.initials: L
authors.lastname: Angelkov
authors.forename: Nada
authors.initials: N
authors.lastname: Kostic
authors.forename: Zorica
authors.initials: Z
authors.lastname: Caparevic
authors.forename: Zorana
authors.initials: Z
authors.lastname: Vasiljevic-Pokrajcic
mesh_terms: D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D025401:Echocardiography, Stress; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011379:Prognosis; D012372:ROC Curve; D016277:Ventricular Function, Left