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MEDIC

MSCT in the Evaluation of Prosthetic
Heart Valves Dysfunction
Nguyen Xuan Trinh, MD
Prof. Pham Nguyen Vinh, MD
Department of Cardiology- Medic Medical Center


Prosthetic Heart Valve (PHV)
MEDIC

 In 2003, approximately 290,000 patients worldwide
underwent heart-valve replacement and received a
Prosthetic heart valve (PHV).

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Type of Prosthetic Heart Valves (PHV)
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Mechanical PHV

Biological PHV


PHV Dysfunction
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 PHV dysfunction is a rare, but potentially

life-threatening complication.
 In clinical practice, PHV dysfunction poses a
diagnostic dilemma.

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


PHV Dysfunction
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 Structural valve dysfunction: degeneration, wear,
fracture, and disc escape.
 Nonstructural dysfunction: pannus formation , paravalvular
leak, inappropriate sizing or positioning of the PHV, residual leak
or obstruction after valve implantation

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Imaging techniques
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 Have a key role in PHV assessment and the detection of
PHV dysfunction: TTE, TEE, 3D-TEE and fluoroscopy.
 Echocardiography and fluoroscopy are the imaging
techniques of choice and are routinely used in daily
practice.
 These techniques sometimes fail to determine the
specific cause of PHV dysfunction.
( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )

Imaging techniques
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 Over the past 2 years, MSCT also has shown potential for
PHV assessment.
 MSCT can be of additional value in diagnosing the specific
cause of PHV dysfunction and provides valuable
complementary information for surgical planning in case of
reoperation.
 Cardiac MRI has limited value in the evaluation of
biological PHV dysfunction.
( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Evaluation of Native or Prosthetic Valves
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

MSCT

With Mechanical PHV, opening and closing angles can be
measured as accurately as with fluoroscopy.

 Biological leaflet thickening or calcification and leaflet

restriction can also be detected.

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


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Residual opening angle
(normal limit ≤ 20°)-MSCT

(Tsai et al. AJR 2011; 196:353–360)


MSCT
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 Promising technique to localize the anatomical
abnormalities causing PHV obstruction (Pannus).
 Enable the differentiation between a pannus and
a thrombus on density

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Disadvantages of MSCT
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 Radiation exposure

 640 slice- MSCT: lower radiation doses

 Need for contrast injection.

 Morbidity and mortality associated with PHV
dysfunction is high and MSCT can help to establish the

exact cause of the dysfunction


Mechanical PHV Obstruction
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 A life-threatening complication
 Caused by thrombosis, pannus formation, interference by
sutures, infectious vegetations and structural PHV
dysfunction.

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Pannus Imaging
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( Amal Ibrahim Khalifa, M.D. Assessment of Prosthetic Valves Prosthetic Malfunction. 3/18/2013)


PHV thrombus
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( Jonathan Chan et al. Circulation. 2009;120:1933-1934 )

Suggested Non-invasive Imaging Protocol in
the Diagnostic Suspected PHV dysfunction
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( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


Biological PHV dysfunction
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 Most notably, biological PHVs degenerate after a variable time
period (10–20 years).
 TTE and TEE are the preferred imaging techniques to assess
biological PHV dysfunction, but both techniques can fail to identify
the exact cause of the PHV obstruction.
 Cardiac MRI and MSCT can have complementary value, especially
by identifying pannus tissue or subvalvular obstruction

( Jesse Habets. Computed Tomography of Prosthetic Heart Valves. 2012 )


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Case 1

 45F, Mechanical AVR and MVR (2009),
 MV Prosthesis were stuck ( 2 times).
 Mechanical AVR and Bio-Prosthetic MV (2009)
 Anticoagulation had been discontinued.

 Upon admission: increased Grd peak/ mean across the
aortic valve: 74/33mmHg
 TTE, TEE, Fluoroscopy, 640-slice MSCT suggestive of prosthetic
valve dysfunction ( Pannus or Thrombus).


Residual Opening Angle
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MSCT Imaging of Mechanical Aortic Valveposterior leaflet restriction
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Pannus Imaging
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MOVIE 1


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Case 2

 62M, Bio-Prosthetic AVR (2011)
 Irregular check up.
 Upon admission: increased Grd peak / mean across the

aortic valve: 220/140mmHg
 TTE, TEE suggestive of prosthetic valve dysfunction (
Subvalvular mass ?)
 640-slice MSCT suggestive of prosthetic valve dysfunction (
leaflet restriction, biological PHVs degenerate ) and severe
paravalvular calcification
 Reoperative repair : 12/ 2013


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Biological PHV
Thickening and
Degenerate


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Biological PHV Thickening and
Degenerate- leaflet restriction