Valvular disease on CT — CCTCore Wiki

CT as the second-line modality after echo — but the gold standard for transcatheter procedure planning, heavy calcification, and prosthetic valve dysfunction.

While echocardiography remains the first-line modality for valvular heart disease, Cardiac CT is a powerful secondary tool when echo or MRI are suboptimal or contraindicated (severe obesity, claustrophobia, incompatible pacemakers).

CT’s primary limitation is temporal resolution (~ 67–165 ms vs echo < 33 ms). But CT provides exceptional spatial resolution — making it the gold standard for transcatheter procedure planning and for evaluating heavy calcification.

1 Aortic valve disease

Aortic valve disease on CT — normal tricuspid valve anatomy, aortic stenosis Agatston score and planimetry, bicuspid aortic valve fish-mouth appearance, aortic regurgitation central regurgitant orifice — Aortic valve disease on CT: normal Y-shaped tricuspid valve, aortic stenosis quantified by Agatston score and orifice planimetry, bicuspid morphology, and aortic regurgitation (central coaptation gap on diastolic phase).

A normal aortic valve is tricuspid and appears Y-shaped during closure.

Aortic stenosis (AS). CT is excellent at quantifying aortic valve calcium (CT-AVC), which correlates directly with severity and is load-independent — making it valuable when echo is discordant:

Sex-specific Agatston thresholds for severe AS: > 1,300 AU in women, > 2,000 AU in men (validated in multicenter cohorts)
Grade stenosis by direct planimetry of the orifice area during maximum systolic opening (typically mid-systole, 20–40% of the R-R interval)
< 1 cm² orifice area generally indicates severe stenosis
A bicuspid aortic valve often presents with a “fish-mouth” appearance during systole — → see Bicuspid aortic valve — types & phenotypes for the 2021 International Consensus nomenclature (fused, 2-sinus, partial-fusion) and the aortopathy phenotypes
→ See CT aortic valve calcification (CT-AVC) for full acquisition protocol, pitfalls, sex-specific thresholds, and clinical use

Aortic regurgitation (AR). On a diastolic-phase CT, AR is diagnosed by visualizing incomplete coaptation of the cusps — a visible central regurgitant orifice.

2 Mitral valve disease

Mitral valve disease on CT — mitral stenosis with thickened calcified leaflets and hockey-stick doming, mitral valve prolapse with systolic bowing into LA, flail leaflet with ruptured chordae — Mitral valve disease on CT: stenosis (commissural fusion, diastolic hockey-stick doming), prolapse (leaflet extension > 2 mm behind the annular plane into the LA), and flail leaflet with ruptured chordae.

Mitral stenosis (MS). Most frequent cause is rheumatic heart disease. On CT, thickened or calcified leaflets with commissural fusion, causing a narrowed orifice and a characteristic diastolic “doming” (hockey-stick appearance) of the anterior leaflet.
Mitral valve prolapse (MVP). The most common cause of mitral regurgitation requiring surgery. CT diagnoses MVP when leaflets demonstrate a systolic “bowing” or extension > 2 mm into the LA behind the plane of the mitral annulus.
Flail leaflets — CT can also detect ruptured chordae.

3 Right-sided valves (tricuspid & pulmonic)

Right-sided valve disease on CT — triphasic protocol, carcinoid heart disease with thickened retracted fixed tricuspid and pulmonic leaflets, Ebstein anomaly with apical displacement of septal leaflet and atrialized right ventricle — Right-sided valve assessment: triphasic contrast technique, carcinoid heart disease (thickened, retracted, fixed leaflets on both tricuspid and pulmonic valves), and Ebstein anomaly (apical displacement ≥ 8 mm/m² BSA with atrialized RV).

Evaluating right-sided valves requires triphasic contrast protocols or delayed scanning to ensure the right heart is adequately opacified without streak artifacts.

Carcinoid heart disease — thickened, retracted, and straightened tricuspid and pulmonic leaflets that become fixed and nonmobile throughout the cardiac cycle.
Ebstein anomaly — apical displacement of the septal tricuspid leaflet (≥ 8 mm/m² BSA), leading to an “atrialized” right ventricle and massive RA enlargement.

4 Endocarditis & valvular masses

Endocarditis and valvular masses on CT — infective endocarditis with vegetation, leaflet perforation, paravalvular abscess and pseudoaneurysm; papillary fibroelastoma with small rounded mass on thin stalk and microlobulated surface — Infective endocarditis (vegetation, leaflet perforation, paravalvular abscess/pseudoaneurysm) and papillary fibroelastoma (small stalked mass with frond-like surface, typically away from leaflet tips — the second most common cardiac tumor).

Infective endocarditis. TEE is most sensitive — but CT can identify vegetations (irregularly shaped, oscillating hypoattenuated masses attached to leaflets), leaflet perforations, and life-threatening paravalvular abscesses or pseudoaneurysms.
Papillary fibroelastoma. The 2nd most common cardiac tumor, often found incidentally on valves. CT shows small, rounded masses with a thin stalk and a microlobulated (frond-like) surface — typically arising away from the leaflet tips.

5 Transcatheter procedure planning

Cardiac CT is strictly mandated for structural interventional planning. Full deep-dive in the dedicated procedure articles, but at a glance:

TAVR. 3D mapping of the non-circular aortic annulus for sizing; coronary-ostia heights to prevent obstruction; iliofemoral access. → TAVR planning
MitraClip & mitral repair. Mitral annulus dimensions; LCx and coronary sinus location; interatrial septum for transseptal puncture; rule out LAA thrombus (absolute contraindication).

6 Prosthetic valve complications

After surgical or transcatheter valve replacement, CT is the most reliable method for evaluating mechanical or bioprosthetic dysfunction:

Finding	What it looks like
Pannus	Fibrous ingrowth — higher density (> 200 HU), typically forming under the prosthesis
Thrombus	Acute clot — lower density (< 200 HU)
HALT	Hypoattenuated Leaflet Thickening on the aortic surface of a bioprosthetic leaflet (post-TAVR)
HAM	Hypoattenuation Affecting Motion — HALT restricting leaflet motion > 50%

HALT and HAM frequently resolve with therapeutic anticoagulation.

CT also vividly visualizes paravalvular leaks, pseudoaneurysms, and valve dehiscence — indicated by a rocking valve motion or a contrast gap between the annulus and the valve margin.