title: Ventricular-arterial uncoupling in heart failure with preserved ejection fraction after myocardial infarction in dogs - invasive versus echocardiographic evaluation.
abstract: BACKGROUND
  Heart failure with preserved left ventricular ejection fraction and abnormal diastolic function is commonly observed after recovery from an acute myocardial infarction. The aim of this study was to investigate the physiopathology of heart failure with preserved ejection fraction in a model of healed myocardial infarction in dogs.
  
  
  METHODS
  Echocardiography, levels of neurohormones and conductance catheter measurements of left ventricular pressure-volume relationships were obtained in 17 beagle dogs 2 months after a coronary artery ligation, and in 6 controls.
  
  
  RESULTS
  Healed myocardial infarction was associated with preserved echocardiographic left ventricular ejection fraction (0.57 +/- 0.01, mean +/- SEM) and altered Doppler mitral indices of diastolic function. NT-proBNP was increased, aldosterone was decreased, and norepinephrine was unchanged. Invasive measurements showed a markedly decreased end-systolic elastance (2.1 +/- 0.2 vs 6.1 +/- 0.8, mmHg/ml, p < 0.001) and end-systolic elastance to effective arterial elastance ratio (0.6 +/- 0.1 vs 1.4 +/- 0.2, p < 0.001), with altered active relaxation (dP/dtmin -1992 +/- 71 vs -2821 +/- 305, mmHg/s, p < 0.01) but preserved left ventricular capacitance (70 +/- 6 vs 61 +/- 3, ml at 20 mmHg, p = NS) and stiffness constant. Among echocardiographic variables, the wall motion score index was the most reliable indicator of cardiac contractility while E', E/A and E'/A' were correlated to dP/dtmin.
  
  
  CONCLUSIONS
  In the canine model of healed myocardial infarction induced by coronary ligation, heart failure is essentially characterized by an altered contractility with left ventricular-arterial uncoupling despite vascular compensation rather than by abnormal diastolic function.
authors.affiliation: Department of Physiology and Pathophysiology, ULB, Brussels, Belgium. myrielle.mathieu@ulb.ac.be
authors.forename: Myrielle
authors.initials: M
authors.lastname: Mathieu
authors.forename: Bachar
authors.initials: B
authors.lastname: El Oumeiri
authors.forename: Karim
authors.initials: K
authors.lastname: Touihri
authors.forename: Ielham
authors.initials: I
authors.lastname: Hadad
authors.forename: Maryam
authors.initials: M
authors.lastname: Mahmoudabady
authors.forename: Philippe
authors.initials: P
authors.lastname: Thoma
authors.forename: Thierry
authors.initials: T
authors.lastname: Metens
authors.forename: Jozef
authors.initials: J
authors.lastname: Bartunek
authors.forename: Guy R
authors.initials: GR
authors.lastname: Heyndrickx
authors.forename: Serge
authors.initials: S
authors.lastname: Brimioulle
authors.forename: Robert
authors.initials: R
authors.lastname: Naeije
authors.forename: Kathleen
authors.initials: K
authors.lastname: Mc Entee
mesh_terms: D000818:Animals; D001026:Coronary Artery Bypass; D003971:Diastole; D004285:Dogs; D004452:Echocardiography; D056966:Excitation Contraction Coupling; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery*; D006334:Heart Function Tests; D006439:Hemodynamics; D006801:Humans; D023421:Models, Animal; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery*; D013318:Stroke Volume