title: Left ventricular function and exercise performance in idiopathic dilated cardiomyopathy: role of tissue Doppler imaging.
abstract: BACKGROUND
  To examine the relationship between left ventricular (LV) function evaluated at echocardiography and exercise performance in idiopathic dilated cardiomyopathy (IDCM) patients.
  
  
  RESULTS
  We enrolled 76 consecutive IDCM patients in sinus rhythm, undergoing cardiopulmonary exercise testing and echocardiography [49 ± 13 years old; LV ejection fraction 31 ± 7%, LV end-diastolic volume 96 ± 31 ml/m; peak oxygen consumption (peak VO2/kg) 18 ± 5.6 ml/kg/min]. Linear regression analysis revealed that peak systolic velocity (S') (r = 0.46; P < 0.001) and E/E' (r = -0.43; P < 0.001), two tissue Doppler imaging derived parameters, were related to peak VO2/kg, whereas ejection fraction and mitral inflow variables were not. Considering the 69 patients (90%) without diastolic restrictive pattern (a well known index of severe diastolic dysfunction), multivariate regression analysis showed that age, E/E' and S' were the only independent variables related to peak VO2/kg. Similarly, age and E/E' were confirmed as independent parameters for the prediction of ventilation/carbon dioxide production slope in the whole population.
  
  
  CONCLUSIONS
  In IDCM patients, cardiopulmonary exercise performance variables were strongly related to E/E' and S'.
authors.affiliation: aCardiovascular Department, 'Ospedali Riuniti'bPostgraduate School of Cardiovascular Sciences, University of TriestecCardiovascular Center, Health Authority No. 1, TriestedCardiologic Center Monzino, IRCCS, Milano, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Zambon
authors.forename: Annamaria
authors.initials: A
authors.lastname: Iorio
authors.forename: Concetta
authors.initials: C
authors.lastname: Di Nora
authors.forename: Cosimo
authors.initials: C
authors.lastname: Carriere
authors.forename: Elena
authors.initials: E
authors.lastname: Abate
authors.forename: Marco
authors.initials: M
authors.lastname: Merlo
authors.forename: Giulia
authors.initials: G
authors.lastname: Barbati
authors.forename: Andrea
authors.initials: A
authors.lastname: Di Lenarda
authors.forename: Bruno
authors.initials: B
authors.lastname: Pinamonti
authors.forename: Piergiuseppe
authors.initials: P
authors.lastname: Agostoni
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Sinagra
mesh_terms: D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015150:Echocardiography, Doppler; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D012042:Registries; D012189:Retrospective Studies; D013318:Stroke Volume; D013997:Time Factors; D016277:Ventricular Function, Left