Role of Cardiac CT in the Evaluation of Valvular Heart Disease

Fig. 1. Stepwise CT image acquisition and reconstruction for cardiac-valve assessment. A. Optimal cardiac-phase selection for valve imaging with ECG-synchronized CT. End-systolic phases (approximately 20%–30% of the R–R interval) are useful for evaluating aortic-valve stenosis and mitral-valve prolapse or regurgitant lesions, whereas mid-diastolic phases (approximately 70%–80% of the R–R interval) are optimal for assessing aortic-valve regurgitation and mitral-valve stenosis. B. Optimal imaging-plane selection for valve evaluation using multiplanar reformation, allows precise alignment either parallel (en face view) or perpendicular to the valvular plane. C. En face multiplanar reconstruction of the cardiac valves, provides a surgeon’s view of the leaflet anatomy and commissural orientation. D. Perpendicular multiplanar reconstruction to the valvular plane, enables detailed assessment of leaflet thickness, motion, and coaptation. E. Thick-slab multiplanar reconstruction in an en face view, offers an overview of the valve and adjacent structures along with measurement of the valve-opening area. F. Volume-rendered images demonstrate 3D visualization of valve anatomy, facilitating intuitive…

Fig. 2. BAV phenotypes based on the international consensus classification. En face views of the aortic valve demonstrate representative BAV morphologies. A. Two-sinus BAV characterized by two symmetrical sinuses without a raphe. B. Fused BAV with R-N cusp fusion and complete raphe. C. Partial-fusion BAV shows incomplete R-L cusp fusion with a small raphe involving <50% of the cusp margin. BAV = bicuspid aortic valve, R-L = right–left, R-N = right noncoronary

Fig. 3. BAV with severe AS and associated aortopathy. A, B. Thick-slab en face multiplanar reconstructions of the aortic valve obtained at systole (A) and diastole (B) demonstrate a two-sinus BAV with markedly restricted systolic valve opening, diffuse leaflet thickening, and calcification. The measured aortic-valve area was 0.851 cm2, consistent with severe AS. C. Multiplanar reconstruction perpendicular to the aortic-valve plane at systole shows dilatation of the ascending aorta, indicating concomitant BAV-related aortopathy. D. 4D flow MRI at systole demonstrates marked flow acceleration at the aortic-valve level (red) with eccentric systolic jet impingement on the anterior wall of the ascending aorta, which supports altered hemodynamics associated with BAV and aortopathy. AS = aortic stenosis, BAV = bicuspid aortic valve

Fig. 4. Cardiac CT findings in aortic stenosis. A. An en face view of the aortic valve reconstructed at systole demonstrates marked restriction of valve opening, with diffuse leaflet thickening and calcification. The inset image at the lower right shows the corresponding diastolic phase for comparison, highlighting the limited systolic excursion of the valve leaflets. B. Multiplanar reconstruction perpendicular to the aortic-valve plane at systole confirms severe limitation of valve opening. C. Thick-slab en face multiplanar reconstruction at systole allows direct planimetric measurement of the maximal aortic-valve area, which measured 0.774 cm2, consistent with severe aortic stenosis. D. A volume-rendered image acquired at systole provides 3D visualization of restricted valve opening and leaflet thickening, with the calcified components highlighted in white. LA = left atrium, LCC = left coronary cusp, LV = left ventricle, NCC = noncoronary cusp, RCC = right coronary cusp

Fig. 5. Cardiac CT and 4D flow MRI findings in aortic regurgitation. A, B. En face views of the aortic valve reconstructed at diastole (A) and systole (B) demonstrate a central coaptation defect with leaflet thickening, indicating incomplete valve closure. C. Thick-slab en face multiplanar reconstruction at diastole allows direct planimetric measurement of the central coaptation defect, which measured 0.307 cm2, consistent with significant aortic regurgitation. D. Volume-rendered image acquired at diastole provides 3D visualization of the central coaptation defect and leaflet thickening, facilitating intuitive assessment of valve morphology. E. Multiplanar reconstruction perpendicular to the aortic-valve plane at diastole reveals degenerative changes of the aortic valve with a central coaptation defect; the arrows indicate degenerative thickening at the leaflet tips. F. 4D flow MRI at diastole demonstrates marked regurgitant flow directed toward the LV posterior wall, consistent with significant aortic regurgitation. LA = left atrium, LCC = left coronary cusp, LV = left ventricle, NCC = noncoronary cusp, RCC = right coronary cusp

Fig. 6. Cardiac CT findings in rheumatic mitral stenosis. A. An en face view of the mitral valve reconstructed at diastole demonstrates leaflet thickening with marked limitation of valve opening. B. Multiplanar reconstruction perpendicular to the mitral-valve plane at diastole further delineates leaflet thickening and restricted valve opening. The inset image in the lower corner shows the corresponding systolic phase for comparison. C. Thick-slab en face multiplanar reconstruction at diastole allows direct planimetric measurement of the maximal mitral-valve opening area, measuring 1.00 cm2, consistent with significant mitral stenosis. D. A volume-rendered image acquired at diastole provides 3D visualization of restricted mitral-valve opening and leaflet thickening, facilitating intuitive assessment of valve morphology. LA = left atrium, LV = left ventricle, RV = right ventricle

Fig. 7. Cardiac CT and 4D flow MRI findings in rheumatic multivalvular heart disease. A, B. En face views of the aortic valve reconstructed at systole (A) and diastole (B) demonstrate a fused bicuspid aortic valve with R-N cusp fusion, along with diffuse leaflet thickening and marked restriction of valve opening; these findings are consistent with rheumatic aortic-valve involvement. C, D. Multiplanar reconstructions perpendicular to the mitral-valve plane at systole (C) and diastole (D) further delineate leaflet thickening and restricted mitral-valve opening with doming. The inset image in panel (D) shows the corresponding en face view of the mitral valve, indicating severe limitation of valve opening. E, F. 4D flow MRI demonstrates abnormal transvalvular hemodynamics, with marked systolic-flow acceleration at the aortic-valve level (E, red circle) and diastolic-flow acceleration at the mitral-valve level (F, red circle); these findings are consistent with combined rheumatic aortic and mitral-valve disease. LA = left atrium, LV = left ventricle, R-N = right noncoronary

Fig. 8. Severe mitral annular calcification. A, B. Non-contrast CT (A) and contrast-enhanced cardiac CT (B) short-axis views demonstrate severe mitral annular calcification circumferentially encircling the entire mitral annulus with extension into the aortomitral continuity. Extensive annular calcification may restrict the posterior mitral leaflet, resulting in degenerative (calcific) mitral stenosis.

Fig. 9. Cardiac CT and 4D flow MRI findings in mitral regurgitation caused by mitral valve prolapse. A. Multiplanar reconstruction perpendicular to the mitral-valve plane at systole demonstrates a coaptation defect caused by prolapse of the posterior leaflet (P2 scallop). B. The corresponding perpendicular view at diastole shows restoration of leaflet coaptation, confirming dynamic systolic prolapse. C. An en face view of the mitral valve reconstructed at systole clearly depicts prolapse of the P2 scallop toward the LA. D. A volume-rendered image acquired at systole provides 3D visualization of P2 prolapse, facilitating intuitive assessment of valve morphology and its spatial relationships to the adjacent cardiac structures. E, F. 4D flow MRI at early systole (E) and late systole (F) demonstrates continuous regurgitant flow from the LV to the LA at the mitral-valve level (red circles), consistent with severe mitral regurgitation, with a calculated mitral regurgitant fraction of 53%. A2 = anterior mitral leaflet middle scallop, LA = left atrium, LAA = left atrial appendage, LV = left ventricle, P2 = posterior mitral leaflet middle scallop

Fig. 10. Cardiac CT findings in tricuspid regurgitation caused by pacemaker-lead impingement. A. An en face view of the tricuspid valve at diastole demonstrates significant annular dilatation (maximum diameter, 46 mm). Severe circumferential mitral annular calcification involving the entire mitral annulus is also noted. B. An en face view at systole shows a central coaptation defect of the tricuspid valve (arrowheads) caused by pacemaker-lead impingement (arrow), resulting in tricuspid regurgitation. C. Multiplanar reconstruction perpendicular to the tricuspid valve at systole also demonstrates a central coaptation defect (arrowheads) due to pacemaker-lead impingement (arrow). D. A volume-rendered image at systole provides 3D visualization of the central coaptation defect (arrowheads) associated with pacemaker-lead impingement (arrow), indicating the regurgitation site. RA = right atrium, RV = right ventricle

Fig. 11. Differentiation between pannus and thrombus in a prosthetic aortic valve. A, C. Pannus formation. (A) En face view and (C) multiplanar reconstruction perpendicular to the prosthetic aortic-valve plane at systole demonstrate circumferential subprosthetic partially calcified soft-tissue thickening (arrowheads and arrows) resulting in narrowing of the valve orifice, consistent with pannus formation. B, D. Prosthetic-valve thrombosis. (B) En face view and (D) multiplanar reconstruction perpendicular to the prosthetic aortic-valve plane at systole show a low-attenuation mass involving the valve leaflets and subprosthetic region (arrowheads and arrows), causing narrowing of the valve orifice, consistent with thrombus (hypoattenuated leaflet thickening).

Fig. 12. Cardiac CT findings for pannus formation causing mechanical prosthetic aortic-valve stenosis. A, B. TTE in the parasternal long-axis (A) and short-axis (B) views indicates pannus formation. Serial follow-up echocardiographic assessments demonstrated progressive elevation of aortic-valve peak velocity and mean pressure gradient, although they offered limited visualization of the mechanical prosthetic valve. C. Multiplanar reconstruction perpendicular to the prosthetic aortic-valve plane at systole demonstrated subprosthetic soft-tissue thickening (arrows) along the sewing ring, resulting in a reduced opening angle of the mechanical valve leaflets. D. An en face view at systole shows circumferential subprosthetic soft-tissue thickening (arrowheads) encroaching the valve orifice, consistent with pannus formation. E. Thick-slab en face multiplanar reconstruction at systole further delineates the extent of subprosthetic pannus (arrowheads) and its relationship with the prosthetic-valve leaflets. F. A volume-rendered image acquired at systole provides 3D visualization of the mechanical prosthetic valve and surrounding pannus tissue, facilitating intuitive assessment of the spatial…