title: Comparison of echocardiography with tissue Doppler imaging and magnetic resonance imaging with delayed enhancement in the assessment of children with hypertrophic cardiomyopathy.
abstract: BACKGROUND
  In children with hypertrophic cardiomyopathy (HCM) there often occurs a non-ischemic pattern of myocardial fibrosis, which could be the cause of impaired left ventricular (LV) diastolic function assessed by tissue Doppler imaging (TDI). The aim of the study was to determine the prevalence of myocardial fibrosis in children with HCM, and to evaluate its relationship with echocardiographic parameters including LV diastolic dysfunction.
  
  
  METHODS
  Sixty-three children with HCM, mean age 12.2 ±4.5 years, underwent magnetic resonance imaging (MRI) and echocardiographic study from January 2010 to April 2014. The results of MRI, echocardiography, and TDI velocities were analyzed and compared between children with and without myocardial fibrosis. Moreover, correlations between the results of echocardiography and MRI were assessed.
  
  
  RESULTS
  Our results showed a significant correlation between magnetic resonance and echocardiographic measurements of septal wall thickness, posterior wall thickness, LV mass and left atrial dimension. Children with myocardial fibrosis (60%) had a significantly thicker interventricular septum (21.3 vs. 1.8 mm;p< 0.0001) and larger left atrial dimension (36.7 vs. 27.8 mm;p= 0.0004) and volume index (42.0 vs. 26.6 ml/m²;p= 0.0011). Tissue Doppler imaging demonstrated significantly decreased lateral E' (9.02 vs. 13.53 cm/s;p< 0.0001) and septal E' (7.05 vs. 9.36 cm/s;p= 0.0082) velocities and a significantly increased transmitral lateral (10.34 vs. 6.68;p= 0.0091) and septal (13.1 vs. 9.8;p= 0.046) E/E' ratio in children with myocardial fibrosis.
  
  
  CONCLUSIONS
  Myocardial fibrosis in children with hypertrophic cardiomyopathy was associated with markers for disease severity such as larger septum thickness, enlargement of the left atrium as well as impairment of left ventricular diastolic function. Tissue Doppler imaging is a helpful tool to detect the presence of left ventricular diastolic dysfunction in children with hypertrophic cardiomyopathy and myocardial fibrosis.
authors.affiliation: Department of Pediatric Cardiology, The Children's Memorial Health Institute, Warsaw, Poland.
authors.forename: Lidia
authors.initials: L
authors.lastname: Ziółkowska
authors.affiliation: Magnetic Resonance Unit, Department of Radiology, Institute of Cardiology, Warsaw, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Petryka
authors.affiliation: Department of Pediatric Cardiology, The Children's Memorial Health Institute, Warsaw, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Boruc
authors.affiliation: Department of Pediatric Cardiology, The Children's Memorial Health Institute, Warsaw, Poland.
authors.forename: Wanda
authors.initials: W
authors.lastname: Kawalec
keywords: hypertrophic cardiomyopathy; left ventricular diastolic dysfunction; magnetic resonance imaging; myocardial fibrosis