title: Is myocardial performance index an independent echocardiographic marker of death in children with idiopathic dilated cardiomyopathy?
abstract: BACKGROUND
  Myocardial performance index (MPI) was reported as a parameter of ventricular systolic and diastolic function, as well as a useful tool to predict the outcome in patients with ventricular dysfunction.
  
  
  OBJECTIVE
  To compare MPI with classical echocardiographic parameters as an independent marker of death in children with idiopathic dilated cardiomyopathy (IDCM).
  
  
  METHODS
  Fifty-five children (13 deaths) underwent 104 echocardiograms from January 1996 to May 2005. Right ventricle (RV) MPI and left ventricle (LV) MPI, and 9 classical echocardiographic parameters (left atrium [LA]/body surface area [BSA], distance between mitral E point and ventricular septum, LV mass/body surface area, RV shortening fraction, LV end-systolic and end-diastolic dimensions/body surface area, LV ejection fraction, fiber circumferential shortening velocity, and mitral deceleration time) were compared. Statistical analysis was performed by chi-square, Pearson's correlation and Student t-test, Kaplan-Meier method, Cox's method, and receiver operating curve (ROC). Statistical significance was considered with alpha<0.05 and p=0.80].
  
  
  RESULTS
  Univariate analysis showed that all studied parameters were markers of death. There was a high correlation between RVMPI and LVMPI (r=0.847]-p=0.0001]); therefore, to avoid bias, RVMPI was discharged from multivariate analysis. In the deceased group, moderate/severe mitral regurgitation was frequent (76.9%; confidence interval [CI[ 95%=46.2%- 94.9%) and it was considered in multivariate analysis. In Cox's multivariate analysis, LVMPI was the only independent marker of death (p=0.0213]). The ideal cut-off was 0.63 with 92.3% sensitivity, 66.7% specificity, and fitted ROC area=0.918].
  
  
  CONCLUSIONS
  In children with IDCM, LVMPI is an independent marker of death.
authors.affiliation: Research Department, National Institute of Cardiology, Rio de Janeiro, Brazil. vitoraze8@hotmail.com
authors.forename: Vitor Manuel P
authors.initials: VM
authors.lastname: Azevedo
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Albanesi Filho
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Santos
authors.forename: Márcia B
authors.initials: MB
authors.lastname: Castier
authors.forename: Bernardo R
authors.initials: BR
authors.lastname: Tura
authors.forename: José Geraldo
authors.initials: JG
authors.lastname: Amino
authors.forename: Maria Ourinda Mesquita
authors.initials: MO
authors.lastname: Da Cunha
mesh_terms: D000293:Adolescent; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography; D006801:Humans; D007223:Infant; D015233:Models, Statistical; D009200:Myocardial Contraction; D012372:ROC Curve; D015996:Survival Rate; D016276:Ventricular Function
references.citation: Circulation. 1998 Apr 7;97(13):1246-56
references.pmid: 9570194
references.citation: Am Heart J. 1991 Jul;122(1 Pt 1):126-31
references.pmid: 1829567
references.citation: Am J Cardiol. 1983 Nov 1;52(8):1084-7
references.pmid: 6637828
references.citation: Am Heart J. 1991 May;121(5):1502-6
references.pmid: 2017982
references.citation: Am Heart J. 1999 Aug;138(2 Pt 1):334-8
references.pmid: 10426848
references.citation: Pediatrics. 1998 Mar;101(3 Pt 1):369-76
references.pmid: 9480999
references.citation: Heart. 2004 Aug;90(8):908-15
references.pmid: 15253966
references.citation: Arq Bras Cardiol. 2000 Mar;74(3):197-208
references.pmid: 10951823
references.citation: Heart. 2003 Oct;89(10):1174-8
references.pmid: 12975411
references.citation: Arq Bras Cardiol. 2004 Jun;82(6):505-14
references.pmid: 15257368
references.citation: J Am Coll Cardiol. 1996 Nov 1;28(5):1226-33
references.pmid: 8890820
references.citation: J Am Soc Echocardiogr. 1998 Sep;11(9):849-56
references.pmid: 9758376
references.citation: Tohoku J Exp Med. 1986 May;149(1):31-7
references.pmid: 3738915
references.citation: Circulation. 1994 Sep;90(3):1310-8
references.pmid: 8087940
references.citation: Rev Esp Cardiol. 1995 Oct;48(10):660-5
references.pmid: 7481034
references.citation: Clin Cardiol. 2008 Sep;31(9):424-30
references.pmid: 18781602
references.citation: J Am Coll Cardiol. 1984 Oct;4(4):715-24
references.pmid: 6207218
references.citation: Pediatr Cardiol. 2002 Sep-Oct;23(5):522-7
references.pmid: 12211201
references.citation: Circulation. 1996 Mar 1;93(5):841-2
references.pmid: 8598070
references.citation: J Am Soc Echocardiogr. 2003 Jul;16(7):777-802
references.pmid: 12835667
references.citation: J Cardiol. 1995 Dec;26(6):357-66
references.pmid: 8558414
references.citation: Eur J Pediatr. 2003 Oct;162(10):690-6
references.pmid: 12905011
references.citation: J Am Soc Echocardiogr. 1999 Dec;12(12):1058-64
references.pmid: 10588781