title: Hemodynamic predictors of aortic dilatation in bicuspid aortic valve by velocity-encoded cardiovascular magnetic resonance.
abstract: BACKGROUND
  Congenital bicuspid aortic valve (BAV) is a significant risk factor for serious complications including valve dysfunction, aortic dilatation, dissection, and sudden death. Clinical tools for identification and monitoring of BAV patients at high risk for development of aortic dilatation, an early complication, are not available.
  
  
  METHODS
  This paper reports an investigation in 18 pediatric BAV patients and 10 normal controls of links between abnormal blood flow patterns in the ascending aorta and aortic dilatation using velocity-encoded cardiovascular magnetic resonance. Blood flow patterns were quantitatively expressed in the angle between systolic left ventricular outflow and the aortic root channel axis, and also correlated with known biochemical markers of vessel wall disease.
  
  
  RESULTS
  The data confirm larger ascending aortas in BAV patients than in controls, and show more angled LV outflow in BAV (17.54 +/- 0.87 degrees) than controls (10.01 +/- 1.29) (p = 0.01). Significant correlation of systolic LV outflow jet angles with dilatation was found at different levels of the aorta in BAV patients STJ: r = 0.386 (N = 18, p = 0.048), AAO: r = 0.536 (N = 18, p = 0.022), and stronger correlation was found with patients and controls combined into one population: SOV: r = 0.405 (N = 28, p = 0.033), STJ: r = 0.562 (N = 28, p = 0.002), and AAO r = 0.645 (N = 28, p < 0.001). Dilatation and the flow jet angle were also found to correlate with plasma levels of matrix metallo-proteinase 2.
  
  
  CONCLUSIONS
  The results of this study provide new insights into the pathophysiological processes underlying aortic dilatation in BAV patients. These results show a possible path towards the development of clinical risk stratification protocols in order to reduce morbidity and mortality for this common congenital heart defect.
authors.affiliation: Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: P Martijn
authors.initials: PM
authors.lastname: den Reijer
authors.forename: Denver
authors.initials: D
authors.lastname: Sallee
authors.forename: Petra
authors.initials: P
authors.lastname: van der Velden
authors.forename: Eline R
authors.initials: ER
authors.lastname: Zaaijer
authors.forename: W James
authors.initials: WJ
authors.lastname: Parks
authors.forename: Senthil
authors.initials: S
authors.lastname: Ramamurthy
authors.forename: Trevor Q
authors.initials: TQ
authors.lastname: Robbie
authors.forename: Giorgina
authors.initials: G
authors.lastname: Donati
authors.forename: Carey
authors.initials: C
authors.lastname: Lamphier
authors.forename: Rudolf P
authors.initials: RP
authors.lastname: Beekman
authors.forename: Marijn E
authors.initials: ME
authors.lastname: Brummer
mesh_terms: D000293:Adolescent; D001011:Aorta / Q000473:pathology* / Q000503:physiopathology; D001018:Aortic Diseases / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D001021:Aortic Valve / Q000002:abnormalities* / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity; D016022:Case-Control Studies; D002648:Child; D004108:Dilatation, Pathologic; D015150:Echocardiography, Doppler; D005260:Female; D006330:Heart Defects, Congenital / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000097:blood; D020780:Matrix Metalloproteinase 9 / Q000097:blood; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012039:Regional Blood Flow; D019714:Tissue Inhibitor of Metalloproteinases / Q000097:blood
chemical_list: D015415:Biomarkers; D019714:Tissue Inhibitor of Metalloproteinases; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9