Computed Tomography and Magnetic Resonance Imaging Findings of Bicuspid Aortic Valve and Related Abnormalities of the Heart and Thoracic Aorta

Fig. 1. Classification of bicuspid aortic valve (BAV) according to the Sievers classification system. Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) images showing BAV type 0, BAV without raphe, lateral cusp orientation (A), and anteroposterior cusp orientation (B). C-E. Axial double-oblique MPR CT images showing the BAV with raphe. C, D: BAV type 1: BAV with one raphe at the congenital fusion of R and N (C, arrow) and congenital fusion of R and L (D, arrow). E: BAV type 2: BAV with two raphes and calcification at the congenital fusion of R and N (short arrow) and R and L (long arrow). This presentation cannot be classified by international consensus. A = anterior cusp, L = left coronary cusp, LA = left atrium, N = noncoronary cusp, P = posterior cusp, R = right coronary cusp, RA = right atrium, RV = right ventricle

Fig. 2. New international consensus for bicuspid aortic valve (BAV). Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) images during systole (A) and diastole (B) showing partial fusion BAV. Axial double-oblique MPR CT images during systole (C) and diastole (D) showing a fused BAV with right-left cusp fusion and a very asymmetrical commissural angle of the non-fused cusp (139°–120°). Axial double-oblique MPR CT images during systole (E) and diastole (F) showing fused BAV and right-left cusp fusion with an asymmetrical commissural angle of the non-fused cusp (159°–140°). Axial double-oblique MPR CT images during systole (G) and diastole (H) showing fused BAV and right-left cusp fusion with a symmetrical commissural angle of the non-fused cusp (180°–160°). Axial double-oblique MPR CT images during systole (I) and diastole (J) showing a fused BAV, right-left cusp fusion with no raphe, and a symmetrical commissural angle of the non-fused cusp. Axial double-oblique MPR CT images showing the two-sinus anteroposterior BAV (K) and two-sinus laterolateral BAV (L). Modified from Michelena et al. [4] Eur J Cardiothoracic Surg 2021;60:448-476, with permission of Oxford…

Fig. 3. Schematic showing asymmetry of the fused bicuspid aortic valve (BAV). Assessing the asymmetry of the fused BAV is important for planning and performing BAV repair in aortic regurgitation. A symmetrical angle is defined as a commissural angle of the non-fused cusp of 160°–180°. An asymmetrical angle is defined as a commissural angle of 140°–159° for a non-fused cusp. A very asymmetrical angle is defined as a commissural angle of 120°–139° for a non-fused cusp. Modified from Michelena et al. [4] Eur J Cardiothoracic Surg 2021;60:448-476, with permission of Oxford University Press.

Fig. 4. Ascending aorta aneurysm and coronary anomaly in a 40-year-old man with severe bicuspid aortic valve (BAV) stenosis. A: Axial double-oblique multiplanar reconstruction computed tomography (CT) image with thick-slab volumetric four-dimensional reconstruction using blood-pool inversion technique showing thickened, calcified cusps of BAV with a raphe between the right and left coronary cusps (arrow). B: Axial double-oblique balanced steady-state free precession cardiovascular magnetic resonance imaging (CMR) image showing thickened cusps of BAV with a raphe (arrow). C: Maximum-intensity-projection contrast-enhanced three-dimensional CMR angiogram of thoracic aorta showing a fusiform aortic aneurysm (double-headed arrow) confined to the tubular portion of the ascending aorta. D: Volume-rendered CT image showing high take-off of the left main coronary artery (white arrow) and right coronary artery (black arrow), which also has anomalous origin from the left coronary sinus with an interarterial course.

Fig. 5. Coronary anomaly in an 81-year-old man with bicuspid aortic valve (BAV). A: Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) image showing type 1 calcified BAV with a raphe (arrow). B: Axial double-oblique maximum intensity projection CT showing the right coronary artery originating from the left sinus of Valsalva with an interarterial course (arrow).

Fig. 6. Coarctation of the aorta and ascending aorta aneurysm in a 48-year-old man with bicuspid aortic valve (BAV). A: Axial double-oblique multiplanar reconstruction computed tomography (CT) image showing pure BAV with thickened calcified aortic cusps without a raphe (arrow). B: Steady-state free precession cine magnetic resonance imaging showing aortic valve stenosis with stenotic jet flow (arrow) to the ascending aortic aneurysm (double-headed arrow). C: Volume-rendered CT image after the ascending aortic graft repair (short arrow) showing coarctation of the aorta (long arrow).

Fig. 7. Ventricular septal defect in a 39-year-old man with bicuspid aortic valve (BAV). A: Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) image in diastole showing type 1 BAV with a raphe (arrow). B: Coronal double-oblique MPR CT showing a perimembranous-type ventricular septal defect (arrow). C: Steady-state free precession cine magnetic resonance imaging showing a signal void due to high-velocity jet flow (arrow) from the ventricular septal defect. D: Maximum-intensity projection contrast-enhanced three-dimensional cardiovascular magnetic resonance angiogram of the thoracic aorta showing a fusiform aortic aneurysm confined to the tubular portion of the ascending aorta (double-headed arrow).

Fig. 8. Aortic stenosis in a 64-year-old man with bicuspid aortic valve (BAV). A: Transthoracic echocardiography (TTE) showing thickened bicuspid aortic valve cusps with reduction of the aortic valve area (AVA) in systole (arrows). B: TTE showing a peak transaortic valve velocity of 2.2 m/s, and an AVA of 0.7 cm2, discordant with the aortic stenosis severity. Ejection fraction was 37.8%, which means low-flow low-gradient aortic stenosis. C: Dobutamine stress echocardiography performed the next day showing a mean pressure gradient increase to > 40 mmHg (56.9 mmHg), a Vmax increase to > 4 m/s (4.9 m/s), and an AVA remaining < 1.0 cm2 (0.94 cm2). The aortic stenosis is considered severe. D: Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) image showing thickened, severely calcified cusps of the pure BAV and reduced aortic valve opening with an AVA of 0.98 cm2 (lined area), corresponding to severe aortic stenosis. E: Pre-contrast axial double-oblique MPR CT image showing severely calcified BAV. The Agatston aortic valve calcium score, calculated from a coronary CT calcium scan, is a score corresponding to severe aortic stenosis (5027.5 AU). AV = aortic valve, PG…

Fig. 9. Spontaneous calcific coronary embolus in a 41-year-old man with calcified bicuspid aortic valve (BAV). A: Axial double oblique multiplanar reconstruction (MPR) computed tomography image showing heavily calcified type 0 BAV (arrows). B: Echocardiographic image showing a heavily calcified aortic valve (arrow). C: Curved MPR image of the right coronary artery (RCA) showing a calcified nodule in the posterior descending artery (arrow). No atherosclerotic plaques are visible at other sites of the RCA. D: Conventional coronary angiography shows a nodular filling defect in the posterior descending artery (arrow), surgically confirmed as a calcific embolism.

Fig. 10. Aortic stenosis with myocardial fibrosis in a 62-year-old man with bicuspid aortic valve (BAV) without coronary artery disease. A: Axial double-oblique multiplanar reconstruction computed tomography (CT) image showing type 1 BAV with a raphe (arrow) and thickened calcified cusps. B: Delayed contrast-enhanced CT showing delayed enhancement of the septal and inferior left ventricular walls (arrows). C: Stress perfusion cardiovascular magnetic resonance imaging (CMR) image showing diffuse subendocardial perfusion defects in the left ventricular wall (arrows). D: Delayed contrast-enhanced CMR image showing delayed mid-wall enhancement in the mid-septum and inferior left ventricular walls (arrows).

Fig. 11. Aortic regurgitation in a 57-year-old man with bicuspid aortic valve (BAV). A: Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) image with thick-slab volumetric four-dimensional reconstruction using the blood-pool inversion technique showing type 1 BAV with a raphe (arrow). B: Three-chamber MPR CT image in the diastolic phase showing a prolapsed cusp with coaptation failure (arrow). C: Three-chamber steady-state free precession cardiovascular magnetic resonance imaging image in the diastolic phase showing an eccentric regurgitant jet flow into the left ventricle (arrow). D: Flow versus time curve (red bar: measured at the left ventricular outflow tract below aortic annulus, blue bar: measured at 1 cm above the sino-tubular junction) over the cardiac cycle showing negative values corresponding to regurgitant blood volume and positive values corresponding to the forward blood volume. The regurgitant fraction measured at the left ventricular outflow tract is 39%, which is moderate degree of aortic regurgitation, and is obtained by dividing the reverse flow (68 mL/beat) by the forward flow (173.7 mL/beat).

Fig. 12. Infective endocarditis in a 58-year-old woman with bicuspid aortic valve (BAV) with a 3-month history of fever and general weakness. A: Axial double-oblique multiplanar reconstruction (MPR) computed tomography (CT) image in the systolic phase showing a BAV with a raphe and small vegetation (arrow). B: Axial double-oblique MPR CT image in the diastolic phase showing small vegetations (arrowheads) on two aortic cusps and incomplete coaptation of the aortic cusps. C: Three-chamber MPR CT image in the diastolic phase showing vegetation (arrows).