Echocardiographic Recognition of the Congenital Bicuspid Aortic Valve

Abstract

SUMMARYTwenty-one patients (age four to 25 years) with bicuspid aortic valves proved by surgery and angiography (12) or angiography alone (9) were studied by echocardiography. Seventeen patients had aortic valve disease (11 stenosis, 6 incompetence) and four had coarctation of the aorta with normally functioning aortic valves. A comparison group of 16 patients (9 with aortic valve disease and 7 without aortic valve disease) who had proven tricuspid aortic valves was also studied. Echocardiograms in tricuspid aortic valve patients showed the closed position of the cusps near the middle of the aortic lumen. In contrast marked eccentricity of the aortic valve cusp echoes in diastole could be demonstrated in all with bicuspid aortic valves. The Eccentricity Index (1/2 aortic lumen diameter/minimum distance of the diastolic cusp echo from the nearest aortic margin) was low (range 1.0-1.25) with tricuspid aortic valves and high (range 1.5-5.6) with bicuspid aortic valves (P < 0.001). This index was not significantly affected following successful valvotomy. Bicuspid aortic valve cusps showed normal systolic motion pattern resulting in marked asymmetry of leaflet images. About half of patients with bicuspid aortic valves also showed multilayered echoes in diastole in the absence of fluoroscopic evidence of valvular calcification. Echocardiography appears to be specific in the recognition of the bicuspid aortic valve.

Ex Vivo Evidence for the Contribution of Hemodynamic Shear Stress Abnormalities to the Early Pathogenesis of Calcific Bicuspid Aortic Valve Disease

“…Although those studies have demonstrated the sensitivity of leaflet tissue to WSS magnitude and pulsatility, the elucidation of the role played by native BAV WSS abnormalities in CAVD pathogenesis has been hampered by the complexity of the native BAV hemodynamic environment and the challenge to replicate it in the laboratory setting. BAV flow visualization [49], radiography [50], [51] and magnetic resonance imaging [52]–[54] have revealed the existence of an elliptical clam-shell shaped orifice, an intrinsic degree of stenosis, an eccentric systolic jet and abnormal downstream helical flow patterns. Our recently published computational work on the comparison of TAV and type-I BAV WSS [55] demonstrated that, while those hemodynamic abnormalities have little impact on the non-coronary BAV leaflet WSS, they significantly affect the pulsatility and magnitude of the WSS on the fused BAV leaflet, which is interestingly the leaflet most vulnerable to calcification [2].…”

Bicuspid Aortic Valve

“…The features of BAV on a TTE include systolic doming, an eccentric closure line in the parasternal long axis views, presence of a single commissural line in the diastolic phase with the occurrence of two cusps and the occurrence of two commisures in the parasternal short axis views [ figure 4] [59,60].…”

Multiple aortic root echoes: Clinical, radiographic, and angiographic correlations

“…Echocardiography was performed using a Smith Kline Ekoline sector scanner and a 2. 25 MHz transducer in a standard manner as previously described." Multiple diastolic aortic root echoes were defined as three or more linear parallel echoes in the root as reported by Gramiak and Shah.12 A typical M-mode echocardiogram in a patient with increased diastolic echoes is seen in Fig.…”