Hemodynamic predictors of aortic dilatation in bicuspid aortic valve by velocity-encoded cardiovascular magnetic resonance.
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.
den Reijer
P Martijn
PM
Leiden University Medical Center, Leiden, The Netherlands.
Sallee
Denver
D
van der Velden
Petra
P
Zaaijer
Eline R
ER
Parks
W James
WJ
Ramamurthy
Senthil
S
Robbie
Trevor Q
TQ
Donati
Giorgina
G
Lamphier
Carey
C
Beekman
Rudolf P
RP
Brummer
Marijn E
ME
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
D015415:Biomarkers; D019714:Tissue Inhibitor of Metalloproteinases; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9