Mitral annular calcification (MAC) involves calcium deposition in the fibrous annulus supporting the mitral valve (MV). When calcification extends onto the leaflets, valve opening can be restricted. The influence of MAC MV geometry on Doppler gradients is unknown. This study describes a novel methodology to rapid-prototype subject-specific MAC MVs. Replicated valves were used to assess the effects of distorted annular-leaflet geometry on Doppler-derived, transmitral gradients in comparison to direct pressure measurements and to determine if transmitral gradients vary according to measurement location. Three-dimensional echocardiography data sets were selected for two MAC MVs and one healthy MV. These MVs were segmented and rapid prototyped in their middiastolic configuration for in vitro testing. The effects of MV geometry, measurement modality, and measurement location on transmitral pressure gradient were assessed by Doppler and catheter at three locations along the MV's intercommissural axis. When comparing dimensions of the rapid-prototyped valves to the subject echocardiography data sets, mean relative errors ranged from 6.2% to 35%. For the evaluated MVs, Doppler pressure gradients exhibited good agreement with catheter-measured gradients at a variety of flow rates, though with slight systematic overestimation in the recreated MAC valves. For all of the tested MVs, measuring the transmitral pressure gradient at differing valve orifice positions had minimal impact on observed gradients. Upon the testing of additional normal and calcific MVs, these data may contribute to an improved clinical understanding of MAC-related mitral stenosis. Moreover, they provide the ability to statistically evaluate between measurement locations, flow rates, and valve geometries for Doppler-derived pressure gradients. Determining these end points will contribute to greater clinical understanding for the diagnosis MAC patients and understanding the use and application of Doppler echocardiography to estimate transmitral pressure gradients.

References

1.
Muddassir
,
S. M.
, and
Pressman
,
G. S.
,
2007
, “
Mitral Annular Calcification as a Cause of Mitral Valve Gradients
,”
Int. J. Cardiol.
,
123
, pp.
58
62
.10.1016/j.ijcard.2006.11.142
2.
Pressman
,
G. S.
,
Agarwal
,
A.
,
Braitman
,
L. E.
, and
Muddassir
,
S. M.
,
2010
, “
Mitral Annular Calcium Causing Mitral Stenosis
,”
Am. J. Cardiol.
,
105
, pp.
389
391
.10.1016/j.amjcard.2009.09.042
3.
Jesri
,
A.
,
Braitman
,
L. E.
, and
Pressman
,
G. S.
,
2008
, “
Severe Mitral Annular Calcification Predicts Chronic Kidney Disease
,”
Int. J. Cardiol.
,
128
, pp.
193
196
.10.1016/j.ijcard.2007.05.015
4.
Baumgartner
,
H.
,
Hung
,
J.
,
Bermejo
,
J.
,
Chambers
,
J. B.
,
Evangelista
,
A.
,
Griffin
,
B. P.
,
Lung
,
B.
,
Otto
,
C. M.
,
Pellikka
,
P. A.
, and
Quiñones
,
M.
,
2009
, “
Echocardiographic Assessment of Valve Stenosis: EAE/ASE Recommendations for Clinical Practice
,”
Eur. J. Echocardiogr.
,
10
, pp.
1
25
.10.1093/ejechocard/jen303
5.
Iung
,
B.
,
Cormier
,
B.
,
Ducimetiere
,
P.
,
Porte
,
J. M.
,
Nallet
,
O.
,
Michel
,
P. L.
,
Acar
,
J.
, and
Vahanian
,
A.
,
1996
, “
Immediate Results of Percutaneous Mitral Commissurotomy: A Predictive Model on a Series of 1514 Patients
,”
Circulation
,
94
, pp.
2124
2130
.10.1161/01.CIR.94.9.2124
6.
Wilkins
,
G. T.
,
Weyman
,
A. E.
,
Abascal
, V
. M.
,
Block
,
P. C.
, and
Palacios
, I
. F.
,
1988
, “
Percutaneous Balloon Dilatation of the Mitral Valve: An Analysis of Echocardiographic Variables Related to Outcome and the Mechanism of Dilatation
,”
Br. Heart J.
,
60
, pp.
299
308
.10.1136/hrt.60.4.299
7.
Nishimura
,
R. A.
,
Rihal
,
C. S.
,
Tajik
,
A. J.
, and
Holmes
, Jr.,
D. R.
,
1994
, “
Accurate Measurement of the Transmitral Gradient in Patients With Mitral Stenosis: A Simultaneous Catheterization and Doppler Echocardiographic Study
,”
J. Am. Coll. Cardiol.
,
24
, pp.
152
158
.10.1016/0735-1097(94)90556-8
8.
Nielsen
,
S. L.
,
Nygaard
,
H.
,
Fontaine
,
A. A.
,
Hasenkam
,
J. M.
,
He
,
S.
,
Anderson
,
N. T.
, and
Yoganathan
,
A. P.
,
1999
, “
Chordal Force Distribution Determines Systolic Mitral Leaflet Configuration and Severity of Functional Mitral Regurgitation
,”
J. Am. Coll. Cardiol.
,
33
, pp.
843
853
.10.1016/S0735-1097(98)00627-5
9.
Llanera
,
M. R.
,
Nance
,
M. L.
,
Streicher
,
J. T.
,
Lima
,
J. A. C.
,
Savino
,
J. S.
,
Bogen
,
D. K.
,
Deac
,
R. F. P.
,
Ratcliffe
,
M. B.
, and
Edmunds
, Jr.,
L. H.
,
1994
, “
Large Animal Model of Ischemic Mitral Regurgitation
,”
Ann. Thorac. Surg.
,
57
, pp.
432
439
.10.1016/0003-4975(94)91012-X
10.
Dixon
,
J. A.
, and
Spinale
,
F. G.
,
2009
, “
Large Animal Models of Heart Failure: A Critical Link in the Translation of Basic Science to Clinical Practice
,”
Circ. Heart Fail.
,
2
, pp.
262
271
.10.1161/CIRCHEARTFAILURE.108.814459
11.
Carpentier
,
A.
,
Adams
,
D. H.
, and
Filsoufi
,
F.
,
2010
, “
Pathophysiology, Preoperative Valve Analysis, and Surgical Indications
,”
Carpentier's Reconstructive Valve Surgery: From Valve Analysis to Valve Reconstruction
, 1st ed.,
A.
Carpentier
,
D. H.
Adams
, and
F.
Filsoufi
, eds.,
Saunders-Elsevier
,
Maryland Heights, MO
, pp.
43
53
.
12.
Rausch
,
M. K.
,
Bothe
,
W.
,
Kvitting
,
J. P. E.
,
Swanson
,
J. C.
,
Ingels
, Jr.,
N. B.
,
Miller
,
D. C.
, and
Kuhl
,
E.
,
2011
, “
Characterization of Mitral Valve Annular Dynamics in the Beating Heart
,”
Ann. Biomed. Eng.
,
39
, pp.
1690
1702
.10.1007/s10439-011-0272-y
13.
Liddicoat
,
J. R.
,
Mac Neill
,
B. D.
,
Gillinov
,
A. M.
,
Cohn
,
W. E.
,
Chin
,
C.
,
Prado
,
A. D.
,
Pandian
,
N. G.
, and
Oesterle
,
S. N.
,
2003
, “
Percutaneous Mitral Valve Repair: A Feasibility Study in an Ovine Model of Acute Ischemic Mitral Regurgitation
,”
Cathet. Cardiovasc. Interv.
,
60
, pp.
410
416
.10.1002/ccd.10662
14.
National Research Council of the National Academies, “Guide for the Care and Use of Laboratory Animals,” National Institutes of Health Publication 85–23, Rev.
1996
, Bethesda, Md: National Institutes of Health.
15.
Allison
,
M. A.
,
Cheung
,
P.
,
Criqui
,
M. H.
,
Langer
,
R. D.
, and
Wright
,
C. M.
,
2006
, “
Mitral and Aortic Annular Calcification Are Highly Associated With Systemic Calcified Atherosclerosis
,”
Circulation
,
113
, pp.
861
866
.10.1161/CIRCULATIONAHA.105.552844
16.
Barasch
,
E.
,
Gottdiener
,
J. S.
,
Larson
,
E. K. M.
,
Chaves
,
P. H. M.
,
Newman
,
A. B.
, and
Manolio
,
T. A.
,
2006
, “
Clinical Significance of Calcification of the Fibrous Skeleton of the Heart and Aortosclerosis in Community Dwelling Elderly. The Cardiovascular Health Study (CHS)
,”
Am. Heart J.
,
51
, pp.
39
47
.10.1016/j.ahj.2005.03.052
You do not currently have access to this content.