title: Abnormal contractile responses during dobutamine stress echocardiography in patients with idiopathic dilated cardiomyopathy.
abstract: BACKGROUND
  In chronic heart failure augmented wall stress leads to increased energy demand. Supply, however, may be reduced due to coronary vasoconstriction and endothelial dysfunction. This might lead to a mismatch between demand and supply. In the present study we further explored the effect of increased demand during dobutamine stress echocardiography.
  
  
  RESULTS
  Sixteen patients with idiopathic dilated cardiomyopathy (mean age 44+/-13 years, New York Heart Association class II-III, mean left ventricular ejection fraction 0.27+/-0.10) underwent dobutamine stress echocardiography (5-40 microg/min per kg bodyweight+atropine if required). Wall motion and thickening was assessed in 16 segments using a four-point scale. Eleven patients (69%) showed regions with worsening of wall motion or a biphasic response during dobutamine infusion. Of the remaining five patients one patient did not show any wall motion changes and one patient showed a partial improvement while only in three patients wall motion improvement in the whole heart was found.
  
  
  CONCLUSIONS
  A majority of patients with idiopathic dilated cardiomyopathy showed decreased wall motion during increased demand, i.e. ischemia-like myocardial contractile responses during dobutamine stress echocardiography. These findings further support the concept that an energy mismatch between demand and supply might play a pathophysiological role in idiopathic dilated cardiomyopathy.
authors.affiliation: Department of Cardiology/Thorax Centre, University Hospital Groningen, P.O. Box 30001, 9700 RB Groningen, The Netherlands.
authors.forename: R M
authors.initials: RM
authors.lastname: de Jong
authors.forename: J H
authors.initials: JH
authors.lastname: Cornel
authors.forename: H J
authors.initials: HJ
authors.lastname: Crijns
authors.forename: D J
authors.initials: DJ
authors.lastname: van Veldhuisen
mesh_terms: D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004280:Dobutamine; D015150:Echocardiography, Doppler / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D011379:Prognosis; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013318:Stroke Volume
chemical_list: D004280:Dobutamine