JACC: CARDIOVASCULAR IMAGING
VOL. 5, NO. 4, 2012
© 2012 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
PUBLISHED BY ELSEVIER INC.
ISSN 1936-878X/$36.00
DOI:10.1016/j.jcmg.2011.12.013
STATE-OF-THE-ART PAPER
A Practical Guide to Multimodality Imaging of
Transcatheter Aortic Valve Replacement
Gerald S. Bloomfield, MD, MPH,* Linda D. Gillam, MD,† Rebecca T. Hahn, MD,†
Samir Kapadia, MD,‡ Jonathon Leipsic, MD,§ Stamatios Lerakis, MD,储¶
Murat Tuzcu, MD,‡ Pamela S. Douglas, MD*
Durham, North Carolina; New York, New York; Cleveland, Ohio; Vancouver, British Columbia,
Canada; Atlanta, Georgia; and Athens, Greece
JACC: CARDIOVASCULAR IMAGING
CME
CME EDITOR: RAGAVEN BALIGA, MD
This article has been selected as this issue’s CME activity,
available online at http://imaging.onlinejacc.org by selecting the CME tab on the top navigation bar.
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To obtain credit for this CME activity, you must:
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CME Objective for This Article: At the end of this
activity the reader should be able to: 1) discuss the
strengths and weakness of imaging modalities for preprocedural assessment including a) determining patient
suitability for the proposed access site, b) ensuring that the
proposed device can be safely and successfully implanted
based on device characteristics and the anatomic relationships between the aortic valve and root, left ventricle (LV)
and coronary ostia, c) selection of device size, and d) for
the development of a procedural plan; 2) select imaging
modalities during transcatheter heart valve implantation
to a) ensure the best prosthesis-patient match, b) assess
THV position and function after deployment, and
c) identify immediate complications; 3) identify imaging
modalities for long term follow up including the
a) assessment of valve hemodynamics including gradients
and effective valve area, b) quantification of valvular and
paravalvular regurgitation, c) determining the effect of
implantation on the disease processes related to outflow
obstruction (such as left ventricular hypertrophy, chamber
remodeling, diastolic and systolic function), d) ongoing
assessment of concomitant pathology, and e) detection of
long term complications such as device migration, thrombus formation, ventricular perforation, mitral valve impingement and endocarditis.
CME Editor Disclosure: JACC: Cardiovascular Imaging CME Editor Ragaven Baliga, MD, has reported that he has no relationships to disclose.
Author Disclosure: Dr. Gillam has a Core Lab Contract with Edwards Lifesciences. Dr. Leipsic has served
on the Speaker’s Bureau and MAB for Edwards Lifesciences and GE Healthcare. All other authors have
reported that they have no relationships relevant to the
contents of this paper to disclose.
Medium of Participation: Print (article only); online (article and quiz).
CME Term of Approval:
Issue Date: April, 2012
Expiration Date: March 31, 2013
442
Bloomfield et al.
Practical Guide to TAVR Imaging
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
A Practical Guide to Multimodality Imaging of Transcatheter Aortic
Valve Replacement
The advent of transcatheter aortic valve replacement (TAVR) is one of the most widely anticipated advances in the care of
patients with severe aortic stenosis. This procedure is unique in many ways, one of which is the need for a multimodality
imaging team-based approach throughout the continuum of the care of TAVR patients. Pre-procedural planning, intraprocedural implantation optimization, and long-term follow-up of patients undergoing TAVR require the expert use of various
imaging modalities, each of which has its own strengths and limitations. Divided into 3 sections (pre-procedural, intraprocedural, and long-term follow-up), this review offers a single source for expert opinion and evidence-based guidance on how to
incorporate the various modalities at each step in the care of a TAVR patient. Although much has been learned in the short span
of time since TAVR was introduced, recommendations are offered for clinically relevant research that will lead to refinement of
best practice strategies for incorporating multimodality imaging into TAVR patient care. (J Am Coll Cardiol Img 2012;5:
441–55) © 2012 by the American College of Cardiology Foundation
Percutaneous placement of aortic valve prostheses is
among the most widely anticipated innovations of
the past decade (1,2). Such success is critically
dependent on careful patient selection, optimal
performance of a complex and technically demanding implantation procedure, and careful postoperative care. Multimodality imaging has emerged as an
important ingredient of each of these steps such
that the care team for patients undergoing percutaneous transcatheter aortic valve replacement
(TAVR) must include skilled and knowledgeable
cardiologists and radiologists able to perform and
interpret a variety of imaging techniques, often in
real time during the implantation procedure and
who have specific expertise in TAVR imaging. The
goal of this review is to comprehensively demonstrate how physicians currently derive multimodality imaging information and integrate it into the
decision-making process for patient care for both
self-expanding and balloon expandable TAVR.
This review offers guidance for future imagers
From the *Division of Cardiovascular Medicine, Duke University Medical
Center, and Duke Clinical Research Institute, Durham, North Carolina;
†Division of Cardiology, Columbia University College of Physicians and
Surgeons, New York, New York; ‡Cleveland Clinic Foundation, Cleveland, Ohio; §Department of Radiology and Medicine, University of
British Columbia, Vancouver, British Columbia, Canada; 储Division of
Cardiology, Emory University Hospital, Atlanta, Georgia; and the ¶Cardiology Clinic, Attikon University General Hospital, Medical School of
Athens, Athens, Greece. Dr. Gillam has a Core Lab Contract with
Edwards Lifesciences. Dr. Leipsic has served on the Speaker’s Bureau and
MAB for Edwards Lifesciences and GE Healthcare. All other authors
have reported that they have no relationships relevant to the contents of
this paper to disclose.
Manuscript received September 27, 2011; revised manuscript received
November 27, 2011, accepted December 13, 2011.
involved in this novel procedure and provides the
basis for standardization of the imaging approach to
TAVR, which has been lacking. In 3 sections
(pre-procedural, intraprocedural, and long-term
follow-up assessments), we highlight the importance of multimodality imaging and, when appropriate, compare the utility of various modalities. In
some instances, local expertise will dictate which
modalities are employed at each stage. It is hoped
that this practical review addresses the requirements
for and utility of multimodality imaging in the
continuum of TAVR patient care.
Pre-procedural Assessment
Multimodality imaging goals. The overall goals of
the pre-procedural assessment are to: 1) ensure
patient suitability for the proposed access site;
2) ensure that the proposed device can be safely and
successfully implanted on the basis of device characteristics and the anatomic relationships between
the aortic valve and root, left ventricle (LV), and
coronary ostia; 3) select the device size; and
4) contribute to the development of a procedural
plan.
Determining eligibility for iliofemoral vascular access.
Vascular access
complications are common in TAVR implantation,
with recently published rates ranging from 6.3% to
30.7% (1,3–5). These rates are influenced by various
clinical factors, screening protocols, and the diameter of the arterial sheaths used. Given this high
burden of vascular injury, increasing the effective-
CONVENTIONAL ANGIOGRAPHY.
Bloomfield et al.
Practical Guide to TAVR Imaging
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
ness of pre-procedural screening of patients for
TAVR is key. This often begins with conventional
angiography, because virtually all patients undergo
assessment of the descending aorta, abdominal
aorta, and iliofemoral system to detect stenosis,
occlusion, and aneurysmal disease of the proposed
access site. Angiography provides a basic assessment
of luminal size but a very limited evaluation of the
presence of atherosclerosis and plaque burden as
well as the degree of vessel tortuosity.
Because of the limitations of angiography, multidetector computed tomography (MDCT) has become
the single most important imaging modality for
examination of the abdominal and iliofemoral arteries. A standardized approach reduces morbidity
and mortality rates from vascular injury (6) and
includes a number of reconstructions, including
3-dimensional (3D) volume rendered imaging,
curved multiplanar reformats, and maximum intensity projection images (Fig. 1). Employing a centerline approach to elongate the vessel image, multiple luminal measurements should be made in a
plane orthogonal to the vessel rather than in the
transverse axial plane. With this approach, MDCT
can evaluate vessel size, degree of calcification,
minimal luminal diameter, plaque burden, and vessel tortuosity and also identify high-risk features
including dissections and complex atheroma. Angulations in the iliofemoral system ⬎90° might
preclude insertion of large-bore catheters or cause
significant vessel trauma. In the absence of severe
calcification, bulky atheromatous burden, or severe
tortuosity, short segments of relatively compliant
artery can be up to 1- to 2-mm smaller in diameter
MULTIDETECTOR COMPUTED TOMOGRAPHY.
than the intended sheath, allowing it to be
safely cannulated (7). Less than 180° of
calcification and eccentric calcification are
less likely to create procedural difficulty
than almost circumferential and luminal
calcification. A sheath/femoral artery ratio
of 1.05 or higher has also been shown to
predict both vascular complications and
30-day mortality (8). Although minimal
vessel diameters have been suggested (7),
as smaller sheaths become available the
optimal vessel diameter is likely to be a
moving target. In general, when imaging
characteristics are unfavorable, alternative
approaches such as transapical, transaxillary,
or direct aortic should be considered
(7,9). It should be emphasized that, as
devices and technology change, the imaging parameters used to assess patient
suitability and access planning might be
modified (6). To help reduce the risk of
contrast-induced nephropathy, protocols
have been published that employ direct
power injection of diluted contrast in the
infra-renal aorta and provide excellent
image quality (6,10).
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ABBREVIATIONS
AND ACRONYMS
AR ⴝ aortic regurgitation
CMR ⴝ cardiac magnetic
resonance
CT ⴝ computed tomography
DVI ⴝ Doppler velocity index
EF ⴝ ejection fraction
EOA ⴝ effective orifice area
LV ⴝ left ventricle/ventricular
LVOT ⴝ left ventricular outflow
tract
MDCT ⴝ multi-detector
computed tomography
P-PM ⴝ prosthesis-patient
mismatch
SAVR ⴝ surgical aortic valve
replacement
STJ ⴝ sinotubular junction
TAVR ⴝ transcatheter aortic
valve replacement
TEE ⴝ transesophageal
echocardiography
THV ⴝ transcatheter heart valve
TTE ⴝ transthoracic
echocardiography
ULTRASOUND. Surface ultrasound of the access site
is not frequently used but can be helpful to assess
vessel size, tortuosity, and calcification and identify
the optimal site for puncture (11). Intravascular
ultrasound is helpful to see the lumen in patients
when there is blooming artifact from calcifications.
Coronary intravascular ultrasound catheters can be
used in the periphery at time of diagnostic coronary
angiography for this purpose.
Figure 1. Multi-Detector Computed Tomography Visualization of Iliofemoral Vasculature
(A) Three-dimensional volume rendered image of the iliofemoral vessels and boney pelvis. This reconstruction provides landmarks to display the site of minimal luminal diameter. (B) Curved multiplanar reformat of the right iliofemoral system in an 84-year-old male with
severe aortic stenosis. The curved multiplanar reformat demonstrates elongation of the arterial system and allows for assessment of luminal diameter and degree of encroachment by calcified plaque in multiple projections.
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Aortic valve and root anatomy and transcatheter heart
valve characteristics. To fully understand the use
Figure 2. Aortic Root Anatomy
(A) Diagram of aortic root anatomy showing coronet shape and location of
various annular planes and coronary ostia relative to leaflet attachments. (B)
Imaging planes and leaflet attachments from (A) shown superimposed on
postmortem specimen. Reprinted, with permission, from Piazza et al. (12).
A-M ⫽ aorto-mitral; VA ⫽ ventriculo-arterial.
Aortic root assessment for TAVR: device sizing and
selection. Imaging of the aortic root and heart for
pre-procedural device sizing and selection and procedural planning and execution is performed with the
goals of: 1) measuring aortic annulus size; 2) measuring leaflet length and calcification; 3) locating the
coronary ostia; 4) identifying other features that might
interfere with successful implantation; and 5) contributing to pre-procedural planning. In particular, a
careful multimodality imaging evaluation with
MDCT, echocardiography, and root angiography will
identify high-risk predictors of complications in advance and might result in patient exclusion or other
anticipatory action.
and value of imaging it is essential to appreciate the
complex anatomy of the aortic valve and root and
the specifications of transcatheter heart valves
(THVs) currently available. The aortic annulus, the
commissures, the sinuses of Valsalva, the coronary
ostia, and the sinotubular junction (STJ) are the
framework in which the valve leaflets are suspended
(12) (Fig. 2). It is well-established that the annulus
is an oval-shaped, 3-pronged coronet with 3 anchor
points at the nadir of each aortic cusp rather than a
cylindrical structure. The attachment of the aortic
cusps is semilunar, extending throughout the aortic
root from the LV distally to the STJ. Two virtual
rings are usually defined: an inferior basal ring
formed by joining the basal attachment of the
leaflets (aortic annulus), and a superior ring at the
top of the crown that is a true ring, corresponding
to the STJ (12) (Fig. 2). The aortic annulus measurement by all modalities is assessed at the lowest
hinge point of the aortic valve leaflets at the virtual
basal plane in systole.
The THV characteristics are also important and
must be integrated with imaging findings (Table 1).
The height of the valve prosthesis and the parts of
the prosthesis that are covered by fabric (the “skirt”)
are important to understand with regard to preprocedural planning and implantation. In the SAPIEN
(Edwards Lifesciences, Irvine, California) valve, the
skirt covers the proximal 2 links, whereas in the
CoreValve (Medtronic, Minneapolis, Minnesota)
the proximal 12 mm are covered, and the valve
leaflets are mounted supra-annularly. This is an
important distinction, because high placement
might interfere with coronary flow and future access
as well as increase the likelihood of significant
paravalvular regurgitation.
Aortic annulus measurement. Accurate aortic annulus measurement is critical for the success of the
TAVR, because the size of the annulus will determine the size of the prosthesis that should be used
Table 1. Device Dimensions and Recommended Echocardiographic Aortic Root Measurements
THV Height
THV Skirt Coverage
Recommended Aortic
Annulus Size
Recommended Annulus
to Ostia Height
SAPIEN 23 mm
14.5 mm
7.74–10.1 mm
18–21 mm
⬎10 mm
SAPIEN 26 mm
16 mm
8.67–11.4 mm
22–24.5 mm
⬎11 mm
CoreValve 26 mm
53 mm
12 mm
20–23 mm
n/a
CoreValve 29 mm
59 mm
12 mm
23–27 mm
n/a
Device dimensions and recommended echocardiographic aortic root measurements for the use of the SAPIEN (Edwards Lifesciences, Irvine, California) and CoreValve
(Medtronic, Minneapolis, Minnesota) transcatheter heart valves (THVs) (from Piazza et al. [12] and Jayasuriya et al. [13]).
Bloomfield et al.
Practical Guide to TAVR Imaging
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
(12,13) (Table 1). Mismeasurement of the annulus
is the most common reason for complications such
as aortic regurgitation (AR) (14). Systolic annulus
measurement can be obtained by virtually any technique, although results differ across modalities in
magnitude and reproducibility, including the ability
to accurately capture the true elliptical anatomy of
the annulus (Online Figs. 1 and 2).
ECHOCARDIOGRAPHY. Echocardiographic measurements of the aortic annulus for selecting THV
size (Table 1) have traditionally used the sagittal
plane acquired from a 2-dimensional (2D) parasternal long-axis image on transthoracic echocardiography (TTE) or a mid-esophageal long-axis transesophageal echocardiography (TEE) image between
120° and 140° (Fig. 3). The annular dimension most
commonly used in decision-making for TAVR bisects
the annulus at its maximum diameter during earlysystole, from the hinge point of the right coronary
cusp to the left-noncoronary commissure. When
the cusps are open in systole, the commissure
measurement is particularly difficult, and care must
be taken not to measure too far into the aortic root.
Transesophageal echocardiography measurements
underestimate cylindrical sizers during surgery (15),
because of the oval shape of the annulus. Biplane
imaging or 3D reconstruction can be used to obtain
measurements in the sagittal and coronal planes.
Finally, TEE imaging of balloon aortic valvuloplasty might help define the annular dimension in
difficult cases.
MDCT. Recent improvements in MDCT spatial and
temporal resolution and higher detector number
systems allow imaging of the aortic root with a
minimal slice thickness of 0.5 to 0.75 mm, resulting
in almost isotropic datasets allowing oblique recon-
Figure 3. Biplane Echocardiographic Imaging Identifies the
Sagittal Imaging Plane That Bisects the Largest Dimension of the
Aortic Annulus
(A and B) Biplane transthoracic imaging shows the sagittal (A) and corresponding transverse (B) plane. The yellow arrows define the imaging
plane for the orthogonal view. The red arrow shows the appropriate
annular measurement in the on-axis sagittal plane. (C and D) Biplane
transesophageal imaging shows the sagittal (C) and corresponding
transverse (D) plane. Red arrow in panel C shows the appropriate
annular measurement in the on-axis sagittal plane.
struction without degradation of spatial resolution.
The aortic annulus plane is obtained by a double
oblique multiplanar reconstruction with 2 orthogonal planes representing the short and long axis of
the virtual basal ring (Fig. 4). Measurements are
taken from systolic phase reconstructions ranging
from 20% to 45% of the R-R interval, during
Figure 4. Measurement of the Aortic Annulus With Multi-Detector Computed Tomography
(A) Coronal plane view through the long axis of the left ventricular outflow tract. The longer dimension of the aortic annulus is depicted
by the red arrow. (B) Sagittal plane view through the long axis of the left ventricular outflow tract. The shorter dimension of the annulus
is depicted by the yellow arrow. Transverse plane reconstructed with the double oblique technique of multiplanar reconstruction (C).
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APRIL 2012:441–55
Table 2. Relative Usefulness of TEE, CT, and CMR for Aortic
Valve and Root Characteristics
Aortic Root Imaging Modality
TEE
2D
CMR
3D
CT
2D
3D
AS severity
⫹⫹
⫹
⫾
⫾
⫾
Aortic valve
morphology
⫹⫹
⫹⫹
⫹
⫾
⫾
Calcium distribution
⫹
⫹
⫹⫹
—
—
Aortic root orientation
—
—
⫹⫹
⫹
⫹⫹
Aortic annulus diameter
⫹⫹
⫹⫹
⫹⫹
⫹
⫹⫹
Aortic root morphology
(size and shape)
⫹⫹
⫹⫹
⫹⫹
⫹
⫹⫹
Coronary ostia to aortic
annulus distance
⫾
⫹
⫹⫹
⫹
⫹⫹
— ⫽ not useful; ⫾ ⫽ limited usefulness; ⫹ ⫽ useful; ⫹⫹ ⫽ very useful; 2D ⫽
2-dimensional; 3D ⫽ 3-dimensional; AS ⫽ aortic stenosis; CMR ⫽ cardiac
magnetic resonance; CT ⫽ computed tomography; TEE ⫽ transesophageal
echocardiography.
retrospective electrocardiographic gating imaging,
using the phase with the maximum valve opening as
is performed in echocardiography. Computed tomography (CT)-based sizing guidelines under development integrate 3D data afforded by CT into
the prosthesis selection process, with recommendations as follows for MDCT mean basal ring measurements: 23-mm valve for annulus ⱖ19.5 to
ⱕ22.5 mm, 26-mm valve for ⬎22.5 to ⱕ26.5 mm,
and 29-mm valve for ⬎26.5 to ⱕ29.5 mm (16).
Cardiac magnetic resonance (CMR) allows for an anatomic and
functional assessment of the aortic valve and aortic
root. However, similar to standard echocardiography, most CMR sequences are 2D with the plane of
imaging chosen at the time of the examination (17).
Whole heart, echo-gated 3D CMR with contrast
and a slice thickness of 1.5 mm, a spatial resolution
of 1 mm in-plane and 1 mm through plane (compared with 0.5 ⫻ 0.5 ⫻ 0.5 mm by MDCT)
provides isotropic images for multiplanar reconstruction and shows the oval shape of the annulus
with maximal and minimal diameters (Online Fig. 2).
CARDIAC MAGNETIC RESONANCE.
mum dimension measured from the anteroposterior
view on cine-angiography. In general, the annulus
size as measured by TTE is 1-mm smaller than
measurements by TEE, and the TEE measurement
is 1.0-mm to 1.5-mm smaller than MDCT measurement (18,19). There are no studies to date
comparing CMR measurements of the annulus
with those by echocardiography or MDCT. Despite these differences, TAVR outcomes with the
conventional anteroposterior (sagittal plane) diameter by TEE are excellent (19), and TTE or TEE
aortic annulus measurement continues to be the
gold standard.
Imaging of the aortic leaflets and coronary ostia. Echocardiography, CMR, or MDCT can be used to
measure the distance from the annulus/leaflet hinge
point to the left main ostium and the length of the
corresponding coronary cusp, important parameters
in planning strategies to reduce the risk of coronary
obstruction (9). Multiplanar 3D techniques (i.e.,
TEE, MDCT, or CMR) allow for reconstruction
of the plane of the coronary ostia with corresponding better visualization and assessment of these
complex structures and their interrelationships (Fig. 5).
Bicuspid aortic valves are considered contraindications to TAVR, although it can be difficult to assess
whether a valve is bicuspid or not when it is heavily
calcified.
Both echocardiography and MDCT can evaluate
the extent, location, and distribution of aortic annulus
and leaflet calcifications, thereby providing important
information for successful implantation, although severe calcification might cause acoustic shadowing with
echocardiography. For this reason and due to the high
spatial resolution of MDCT, this method is currently
the test of choice in quantifying severity and identifying the location of aortic cusp calcification. Because of
the signal void caused by calcium, CMR is not a
suitable choice. Multimodality imaging also provides
valuable information about the distribution and extent
Table 3. Comparative Test Characteristics of TEE, CT,
and CMR for Aortic Root Imaging
COMPARISON OF AORTIC ANNULUS MEASUREMENTS
Every technique has its
advantages and disadvantages (Tables 2 and 3), and it
often falls to the operator and to local expertise to
make the safest and most cost-effective choice. The
sagittal plane measurement of the aortic annulus by
TTE and TEE usually approximates the minor axis
of the elliptically shaped annulus as measured by
MDCT. The coronal plane is typically the major
(larger) dimension and corresponds to the maxi-
Aortic Root Imaging
BY TTE, TEE, CMR, AND MDCT.
CMR
TEE
CT
2D
3D
Radiation
No
Yes
No
No
Contrast
No
Yes
No
Yes
Cost
Lower
Higher
Higher
Higher
Length of test
Longer
Very short
Longer
Longer
Yes
No
No
No
Need for sedation
Abbreviations as in Table 2.
Bloomfield et al.
Practical Guide to TAVR Imaging
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
of calcification in other areas, such as the mitral
annulus. For example, dense calcification in the intertrigonal area (the aortomitral curtain) increases the
risk of paravalvular AR due to asymmetric expansion
of the stented valve (20).
Concomitant cardiac pathology. The degree of LV
hypertrophy, particularly upper septal hypertrophy
and the angle between the aorta and the LV are
important in planning the TAVR procedure. A
septal bulge protruding into the left ventricular
outflow tract (LVOT) provides a challenge to the
operator in the accurate placement of the valve and
presents a significant risk of THV repositioning
with cessation of the pacing run. Left ventricular
dysfunction also influences the strategy of the procedure. For instance, in patients with severely depressed LV function, the number of pacing runs
should be minimized to avoid hemodynamic compromise. The degree of baseline AR should be
evaluated, because balloon dilation might worsen
the regurgitant lesion and cause hemodynamic
compromise (21). In these cases, the team should be
prepared to implant the valve expeditiously. Because catheters and wires are placed in the ventricle,
mitral valve compromise might occur at any point
in the procedure and therefore the severity of mitral
regurgitation should be routinely assessed at baseline and throughout the procedure.
Routine and “Interventional” Imaging During THV
Implantation
Multimodality imaging goals. The goals of multimo-
dality imaging in the implantation phase include: 1)
ensuring the best prosthesis-patient match; 2) assessing
THV position and function after deployment; and
3) identifying immediate complications.
Figure 5. Localization of the LM Coronary Artery by Multi-Detector
Computed Tomography and 3D TEE
(A) Multi-detector computed tomography imaging used to acquire the plane
of the left main (LM) coronary artery, with yellow arrow indicating the distance from the hinge point of the left coronary cusp to the LM, and red
arrow indicating the length of the left coronary cusp. (B) Multiplanar reconstruction of a 3-dimensional (3D) transesophageal echocardiography (TEE)
volume set in the transverse plane. The blue arrow shows the plane of the
LM coronary artery. (C) Multiplanar reconstruction of a 3D TEE volume set
showing the plane of the LM ostium and coronary artery. This plane is used
to measure the length of the left coronary cusp (red arrow) and the distance from the hinge point of that cusp to the LM coronary ostium (yellow
arrow) in systole. Ao ⫽ aorta; LV ⫽ left ventricle.
Ensuring proper placement. ANGIOGRAPHY. Proper
valve placement depends on knowledge of the exact
location and orientation of the annular plane, which
should be precisely defined either by angiography or
CT scan before the procedure (22,23) and overlaid
on the screen with fluoroscopy (24) (Fig. 6). Rotational angiography with pacing might also help to
define this plane (25) (Online Fig. 3 and Video 1).
Figure 6. Determination of the Aortic Plane With Pre-Procedural Computed Tomography Scan and Angiography
(A) Three-dimensional computed tomography reconstruction demonstrating the aortic plane running from right anterior oblique (RAO)
caudal to left anterior oblique (LAO) cranial angles. (B and C) Aortic root injection in LAO (B) and RAO (C) views demonstrates the aortic
valve plane with location of each leaflet, respectively. LCC ⫽ left coronary cusp; NCC ⫽ noncoronary cusp; RCC⫽ right coronary cusp.
See Online Video 1.
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Figure 7. Transesophageal Echocardiography Biplane Imaging to Assess
Annular Dimensions and Predict Aortic Regurgitation
(A) Biplane imaging during balloon inflation. The green arrows identify the
waist of the balloon at the level of the annulus. The blue arrow shows
asymmetric balloon dilation at the commissure between the left and noncoronary cusps. The yellow arrows depict acoustic shadowing, which prevents adequate visualization of the peri-balloon region (see Online Video 2
for a moving image of using balloon aortic valvuloplasty for sizing). Biplane
imaging immediately after transcatheter aortic valve replacement of the
case from (A) shows aortic regurgitation at the sites predicted during balloon aortic valvuloplasty (red arrows) (B). See Online Video 2.
In addition to fluoroscopic visualization of balloon
inflation (Online Fig. 4), injection of contrast at the
time of placement is helpful to make final adjustments as necessary with slow balloon inflation and
for the final confirmation of the valve position. The
CoreValve (Medtronic) can be pulled up while
being deployed, if it is thought to be too deep in the
ventricle.
ECHOCARDIOGRAPHY. Transesophageal echocardiography provides continuous real time visualization of the annulus, valve, and balloon, thereby
aiding device placement and prediction and immediate detection of AR. The desired “50-50” positioning of the SAPIEN (Edwards Lifesciences)
valve within the LVOT and aortic root depends on
proper identification of the hinge points of the
native aortic valve leaflets and its relation to the extent
of the prosthesis above or below that point. This
landmark is not optimal, because the hinge points are
not all at the same level within the oval-shaped
annulus and at times can be difficult to visualize.
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Side-to-side exploration or biplane imaging might
minimize some of these limitations. Experience with
intracardiac echocardiography is limited.
Differentiating the valve and balloon just proximal to the valve with imaging can be difficult. To
overcome this, the operator can compare the length
of the stent segment by echocardiography with
known stent length to confirm that the stent is
identified accurately. Transesophageal echocardiography can also be used to assess whether the
delivery system, including the valve, is coaxial to
the LVOT. The tips of the leaflets provide
another echocardiography landmark necessary to
make sure that the distal end of the SAPIEN
(Edwards Lifesciences) stent covers the tip of
native aortic valve, although the trajectory of the
delivery system in relation to the LVOT can also
affect this interpretation.
Preventing, detecting, and managing AR. Transesophageal echocardiography is particularly useful in predicting and managing acute AR (1,26,27). When it
is suspected that asymmetric calcification might affect
final THV shape, imaging during balloon aortic valvuloplasty can be used to localize regions of asymmetric dilation and thus predict the localization of postTAVR AR (Fig. 7) (Online Video 2).
Although minor AR is common after TAVR,
moderate or severe AR is not common, occurring in
5% to 22% of cases (28,29). For both types of
THVs, the most important determinants of postTAVR AR are: undersizing of the prosthesis, the
extent of calcification of the valve, and the prosthesis position in relation to the annulus (30). Studies
of the SAPIEN valve (Edwards Lifesciences) (14)
showed that the cover index (calculated as the
difference between the prosthesis diameter and
TEE annulus diameter, divided by the prosthesis
diameter) is also an important predictor of postTAVR AR. Moderate or greater AR was never
observed in patients with a cover index ⬎8% (i.e.,
valve diameter ⬎8% larger than the measured
annulus) (14). Valve anatomy, severity of calcification, symmetry of valve opening, as well as the angle
of the LVOT/aorta have also been described by
others as potential determinants of post-TAVR AR
for the self-expanding valve (31).
To prevent paravalvular leak, the covered part of
the prosthesis must be well-apposed to the native
leaflets and interleaflet triangles. The ventricular
edge of the device must be just below the hinge
points of the aortic valve. If the balloon-expandable
valve is placed too deep within the LV, it can
potentially embolize into the ventricle but more
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commonly might leave native leaflets uncovered,
creating leaflet overhang—which alters the hemodynamic status of THV valve closure and causes
significant central AR. If the valve is placed too
high within the aorta, it can potentially embolize
into the aorta, resulting in coronary artery obstruction or significant paravalvular regurgitation by
leaving significant portions of the valve apparatus
uncovered by the stent.
Placement of a self-expanding valve too deeply
into the ventricle can also cause considerable AR
through the uncovered part of the prosthesis (32).
Impingement and injury of the anterior leaflet of
the mitral valve is also a concern for “deeply” placed
valves. There is potential for paravalvular AR if 1 of
the commissures is not covered by the stent due to
high positioning. Alternatively, central AR can
result if the stent is “flared” too much on the aortic
side due to high positioning.
Immediately after valve deployment, TAVR
stent positioning, shape, leaflet motion, and AR can
rapidly be assessed with TEE imaging in biplane
mode (Fig. 7) or a single plane short-axis view (33).
For paravalvular regurgitation, the short-axis plane
of imaging should be just below the TAVR stent
and skirt and just within the LVOT; if the imaging
plane is above the stent, regurgitation might not be
visualized or color flow just above the annulus but
contained within the sinuses of Valsalva might be
mistaken for regurgitant jets into the LV. Confirmation of the severity of AR should always be
performed from multiple echocardiographic views.
The deep gastric view allows imaging of the LVOT
without acoustic shadowing (Fig. 8). Imaging the
entire annulus is mandatory and requires rotating
180° while centered on the valve. The severity of
AR typically lessens over the next 30 min after
implantation. Thus, small central or paravalvular
regurgitant jets are commonly seen and do not
require intervention. Patients with more than mild
paravalvular regurgitation, however, could be considered for a second balloon dilation (Online Fig. 5
and Online Videos 3 and 4). In many instances,
post-deployment balloon dilation results in an immediate reduction in paravalvular regurgitation.
Other TAVR implantation complications. The diagnostic considerations in a severely hypotensive patient with post-deployment cardiovascular collapse
are not limited to AR, and real time multimodality
imaging can detect and guide the management of
many of them. The differential diagnosis includes
coronary artery obstruction, pericardial tamponade,
severe mitral regurgitation, aortic dissection, LV dam-
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Figure 8. Deep Gastric Transesophageal Echocardiography Views to Visualize
Paravalvular Aortic Regurgitation
Deep gastric transesophageal echocardiography views of post-transcatheter heart valve
paravalvular aortic regurgitation (red arrows). Biplane imaging or a full rotation to
image 360° of the annulus are required to fully assess the type and severity of aortic
regurgitation. See Online Videos 3 and 4 to see how TEE demonstrates reduction of
paravalvular aortic regurgitation after a second balloon inflation.
age or perforation or rupture, and embolization of the
THV (34). As such, TEE or fluoroscopy can yield the
diagnosis within seconds by demonstrating a wall
motion abnormality, large pericardial effusion, color
flow signal of severe regurgitation, dissection of the
ascending aorta or rupture of the annulus, and the
location of the THV, respectively (Online Videos 5, 6,
7, and 8 for selected examples). Because of the
implantation positioning of the ventricular portion of
the self-expanding valve, there has been a higher
reported incidence of heart block (32).
Long-Term Follow-Up
Multimodality imaging goals. The goals of postimplantation imaging include: 1) assessment of
valve hemodynamic status, including gradients and
effective valve area; 2) quantification of valvular and
paravalvular regurgitation; 3) determination of the
effect of implantation on the disease processes
related to outflow obstruction (such as LV hypertrophy, chamber remodeling, diastolic and systolic
function); 4) ongoing assessment of concomitant
pathology; and 5) detection of long-term complications such as device migration, thrombus formation, ventricular perforation, mitral valve impingement, and endocarditis.
Evaluation of post-implantation THV function. Echocardiography is the imaging modality of choice for
long-term surveillance, because it provides substantial benefits over other techniques, including widespread availability, lack of need for ionizing radia-
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tion, and ability to image structures as well as
accurately measure hemodynamic status. Furthermore, both the SAPIEN (Edwards Lifesciences)
and CoreValve (Medtronic) systems have good
ultrasound imaging characteristics such that a detailed assessment of position, hemodynamic status,
and of the types and degrees of AR with TTE is
possible without significant acoustic shadowing
(35,36) (Online Videos 9 and 10).
However, MDCT and CMR are playing larger
roles in the post-procedural evaluation of TAVR
patients, allowing the evaluation of structural integrity, sphericity, position, aortic regurgitant volume,
and post-procedural complications (5) (Online Fig.
6). These modalities also afford excellent anatomic
detail, allowing for simultaneous assessment of the
prosthesis and its relationship to the native valve,
root, and ventricle as well as detecting pseudoaneurysms of the root or apex and other rare complications (Fig. 9 and Online Fig. 7).
EVALUATION OF MYOCARDIAL FUNCTION AND HE-
Left ventricular mass regression and improvement in ejection fraction (EF)
have been well-documented in patients after surgical aortic valve replacement (SAVR) for aortic
stenosis (37). Similarly, in patients undergoing
TAVR there are reductions in LV mass, modest
improvement in EF (38), and improved diastolic
function (39), and mitral regurgitation might improve (40). A recent comparison of SAVR with
TAVR in patients with low EF showed a greater
increase in EF in the TAVR group (41). The LV
mass, size, and diastolic and systolic function
MODYNAMIC STATUS.
Figure 9. Pseudoaneurysm of the Aortic Root Visualized by
Multi-Detector Computed Tomography
Coronal multiplanar reconstruction of the aortic root in an
89-year-old female patient 3 days after transcatheter aortic valve
replacement. Difficulties with the rapid ventricular pacing were
encountered, resulting in a low deployment, root injury, and a
resultant pseudoaneurysm (arrow). See Online Videos 5, 6, 7,
and 8.
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should thus be followed routinely after TAVR to
quantify the late effects of the hemodynamic
improvement. Echocardiography is the imaging
modality of choice in evaluating LV mass (42);
however, LV mass by CMR also offers a highly
accurate estimate (43).
GRADIENTS, VALVE AREA, AND DIMENSIONLESS
INDEX. Key metrics of prosthetic valve function
include mean and peak transvalvular pressure gradients and the derived indexes of effective orifice
area (EOA) and Doppler velocity index (DVI) (36).
Determination of valve gradients with continuous
wave Doppler is relatively straightforward, noting
that suprasternal notch and right parasternal windows and imaging and nonimaging Pedoff probes
should be routinely used to ensure that maximal
gradients are captured. Both the SAPIEN (Edwards Lifesciences) and CoreValve (Medtronic)
have excellent flow characteristics with mean gradients of 10 to 15 mm Hg (Table 4) (44,45). The
3-year results from a balloon-expandable valve (5)
suggest that a small increase in mean transvalvular
gradient (3.8%/year) and a small reduction in valve
area (0.06 cm2 /year) might occur over time.
Although calculations of EOA and DVI provide
flow-independent indexes of valve function, they
are more challenging to perform in THV than for
conventional surgical prostheses because the supporting stent creates acceleration at both the level of
the stent and within the stent at the level of the
cusps (46) (Fig. 10). This unique flow characteristic
and the potential for variability in cross-sectional
area calculations make it imperative that the subvalvular velocities used in either the DVI or EOA
be routinely sampled proximal to the stent. Sampling within the stent will result in an overestimation of valve area or DVI. Additionally, inconsistent
sampling sites (within the stent at 1 time, below the
stent at another) will result in variable valve areas
that might be misinterpreted as changing valve
hemodynamic status.
The projection of the stent into the LVOT can also
lead to confusion as to the optimal site for measuring
LVOT diameter. Because there is reduced variability
and better correlation with transvalvular gradients
when EOA is calculated with diameters measured
immediately proximal to the stent (47), optimal assessment of EOA and DVI for the SAPIEN valve
(Edwards Lifesciences) should employ velocities and
diameters obtained proximal to the valve stent. The
flow characteristics of the CoreValve (Medtronic) and
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Table 4. Selected Published Gradients for the Edwards SAPIEN and Medtronic CoreValve Transcatheter Heart Valves
Sample Size
Mean Gradient (mm Hg)
EOA (cm2)
SAPIEN Leon (1)
144
11.4 ⫾ 7.0
1.5 ⫾ 0.4
30 days*
88
13.2 ⫾ 11.2
1.6 ⫾ 0.5
1 yr*
SAPIEN Smith (2)
287
9.9 ⫾ 4.8
1.7 ⫾ 0.5; (n ⫽ 279)
30 days*
246
10.2 ⫾ 4.3
1.6 ⫾ 0.5; (n ⫽ 219)
1 yr*
70
10.0 (8–12)
1.7 ⫾ 0.4
Hospital discharge
37
12.1 (8.6–16.0)
1.4 ⫾ 0.3
3 yrs
126
8.5 ⫾ 4.0
NR
30 days
126
9 ⫾ 3.4
NR
2 yrs
51
16 ⫾ 0.5
1.96 ⫾ 0.3
1 yr
Valve and Reference #
SAPIEN Gurvitch (5)
CoreValve Buellesfeld (44)
CoreValve Gotzmann (45)
Follow-Up Period
Mean gradient is mean ⫾ SD or interquartile range. *Core laboratory-adjudicated measurement.
EOA ⫽ effective orifice area; NR ⫽ not reported.
the optimal site for measuring LVOT diameter for
this THV have not been reported.
Prosthesis-patient mismatch (P-PM) occurs
when the EOA of the implanted prosthesis is too
small in relation to body size, and severe P-PM is
defined by an EOA ⱕ0.65 cm2/m2. The P-PM
determines morbidity (48), LV mass regression
(49), and mortality (50) after SAVR. A considerable proportion (20% to 70%) of patients have
P-PM after open aortic valve replacement (30), but
this seems to be less of a problem after TAVR with
CoreValve (Medtronic) or SAPIEN (Edwards
Lifesciences) THVs (P-PM incidences 16% to 32%
and 6%, respectively) (30,51,52). Given that the
experience with TAVR is still growing, the longterm imaging assessments after TAVR should include a thorough examination to document the
presence or absence of P-PM to understand the
potential clinical significance of P-PM in this population.
PARAVALVULAR, TRANSVALVULAR, AND TOTAL AR.
Both transvalvular and paravalvular AR might be
seen after TAVR, with mild or less being the most
common severity found for either THV (26,28).
Differences between the balloon-expandable (SAPIEN [Edwards Lifesciences]) and self-expanding
valves (CoreValve [Medtronic]) have not been fully
characterized; however, in 1 registry (53) there was
an insignificant but higher odds ratio for significant
AR with the self-expanding valve. Follow-up echocardiograms should identify the presence, location,
and severity of both types of regurgitation. The
optimal views for detection of regurgitant jets include the parasternal long-axis, short-axis, apical
long-axis, and 5-chamber views, although— due to
Figure 10. Schematic and Examples of Spectral Doppler Flow Acceleration in a SAPIEN Transcatheter Heart Valve
(A) Schematic presentation of echocardiographic pulse-wave (PW) Doppler patterns when the sample volume is placed pre-stent, in-stent
but pre-cusps, and continuous wave (CW) through the aortic valve. Due to flow acceleration, it is imperative that the subvalvular velocities used in either Doppler velocity index or effective orifice area be sampled proximal to the stent. (B) The PW Doppler pattern of a
sample volume placed before stent. White arrows show the extent of the transcatheter heart valve in the aortic root. Red arrow shows
the level of the prosthetic aortic cusps. (C) The PW Doppler pattern of sample volume placed within the stent but before cusps. (D) The
PW Doppler pattern of a sample volume placed at the level of the cusps. See Online Videos 9 and 10.
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eccentric jets— off-axis views should also be used to
ensure accurate determination of the location and
severity of regurgitation. Color and spectral Doppler techniques are applied in a manner similar to
that of other prosthetic aortic valves (36), with
determination of flow convergence, measurement of
the vena contracta, and extent of regurgitation into
the LV and spectral Doppler parameters such as the
pressure half-time and holodiastolic flow reversal
into the descending aorta. Because both types of
regurgitation affect LV hemodynamic status, a
summary measurement of regurgitation, or “total
AR,” should routinely be calculated and measured
as outlined in the following text.
Significant transvalvular AR after TAVR is usually due to valvular damage during the implantation
procedure, too large a prosthesis for a small annulus
Figure 11. Severity of Aortic Regurgitation Varies in Different Echocardiographic
Windows
(A) Paravalvular aortic regurgitation seems trivial in the short-axis view at the level of
the aortic annulus. (B) Paravalvular aortic regurgitation grade is moderate in this off-axis
apical 5-chamber view of the same patient.
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resulting in valve deformation, or severe calcification of the native valve leading to deformation of
the frame of the THV (54). Short-axis and off-axis
views can be especially helpful to characterize the
origin of the jet passing through the prosthetic
leaflets. With eccentric transvalvular AR jets, care
should be taken to measure the vena contracta in
the correct plane, because measurements of regurgitant jet width parallel to the LVOT measurement
risk overestimating the degree of regurgitation.
With the recent prosthetic valve guidelines, transvalvular
AR should be reported as: 1) mild; 2) moderate; or 3)
severe (55). Trivial or trace regurgitation might also be
noted.
Paravalvular AR (or paravalvular leak, perivalvular leak, or paraprosthetic regurgitation), in contrast
to transvalvular AR, is usually caused by incomplete
prosthesis apposition to the native annulus due to
remaining material of the native valve or ridges of
calcium, too small a prosthesis for a large annulus,
or too-low implantation of the valve leading to
paravalvular leakage through uncovered portions of
the prosthesis (54,56). Because paravalvular AR jets
travel along the natural curvature of the prosthesisannular interface, imaging in multiple planes is
necessary (Fig. 11) and might be difficult to differentiate from transvalvular AR. The transthoracic
short-axis view is usually the best to view the true
orifice of paravalvular AR and helps to prevent the
overestimation of AR severity that can occur when
relying solely on apical views. With recently proposed criteria for standard endpoint definitions for
TAVR clinical trials, the circumferential extent of
paravalvular AR can be graded with ⬍10% being
associated with mild paravalvular AR, 10% to 20%
being associated with moderate, and ⬎20% being
associated with severe AR (55) (Fig. 12). As with
all AR parameters, the approximation of circumferential extent should be weighed with all other
available criteria for assessing the degree of regurgitation.
The total amount of regurgitation is the most
important factor with regard to the hemodynamic
response to the increased volume load, which in
turn might affect chamber dilation, LV function,
and development of pulmonary hypertension (57).
Combining information from color and spectral
Doppler for both transvalvular and paravalvular AR
with established grading criteria, the total AR
should be part of the routine assessment after
TAVR as an assessment of the total volume load. In
most cases, this will be equal to the most severe
degree of AR of either transvalvular or paravalvular
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AR. However, in some instances, the addition of
the 2 flows will push the grading to the next level of
severity (e.g., mild transvalvular AR plus mildmoderate paravalvular AR are graded as moderate
total AR).
Quantitative assessments of regurgitant fraction
and regurgitant volume can also be helpful in
determining the severity of total AR (55). CMR
might be a useful supplement to echocardiography and might be the modality of choice when
the degree is severe or when there is discordance
in grading from different echocardiographic windows (58).
Multimodality imaging research opportunities in
TAVR. There is rich opportunity for research in
multimodality imaging related to TAVR, especially
because most work to date has been observational
and limited to a single THV device. As experience
develops, it follows that prospective studies should
be performed to compare different imaging strategies and different THV devices. Along with this
work, the trial endpoints and methodologies proposed by the Valve Academic Research Consortium
(55) and/or used by TAVR core laboratories need
to be validated to guide future clinical trials, observational studies, and state-of-the-art clinical practice.
Finally—although substantial redundancy in imaging with multiple techniques to assess the same
structures or frequently repeated tests is warranted initially—as experience grows, developing
a rational algorithm for imaging use both before
and after implant will become a priority.
There are also specific research opportunities at
each phase of TAVR patient care. Techniques for
pre-procedural assessment can be refined and employed in systematic comparisons of the accuracy of
different techniques in determining parameters,
such as annular dimensions and annulus to left main
coronary distance (e.g., a multi-center study that
randomizes patients to receive either annular sizing
with MDCT or echocardiography). Assessment of
the relative value of multimodality imaging findings
to select the optimal THV device as well as predictors of subsequent implantation success and complications are other important areas of investigation.
Much of the utility of imaging during implantation comes from offering real time guidance of the
procedure, including rapid detection of malpositioning and complications. Because of the novelty
of TAVR, case reports and case series with imaging
are helpful to document the range of complications
and to educate less experienced implanting teams.
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Figure 12. Grading Criteria for Paravalvular AR
(A) Schematic and illustrated representation of the short-axis view at the
level of the aortic valve by echocardiography. (B) Echocardiographic and
schematic illustrations of the short-axis view of the aortic valve. Paravalvular
aortic regurgitation (AR) can be graded according to the circumferential
extent of the regurgitant jet. Paravalvular AR can be graded as mild, moderate, or severe on the basis of a circumferential extent of ⬍10%, 10% to
20%, or ⬎20%, respectively. See Leon et al. (55). RV, right ventricle. Image
credit: CC Patrick J. Lynch and C. Carl Jaffe, Yale University, 2006.
The post-implantation THV assessments detailed here reflect expert consensus, and their utility
should be validated by comparison with other techniques and long-term outcomes. This is particularly
true for quantitative assessments of paravalvular,
transvalvular, and total AR—which might differ
slightly between devices—and the impact of total
AR on long-term cardiac structure, function, and
clinical outcomes. With regard to AR, more specific, reproducible, and quantitative criteria need to
be developed. Comparison of regurgitant volumes
obtained by 2D and 3D TTE and TEE, quantitative Doppler, and CMR as well as consideration of
invasive and hemodynamic correlates will be informative and might refine the perceived significance
of this complication. The long-term clinical impact
of relief of pressure overload on regression of LV
hypertrophy, chamber remodeling, diastolic and
systolic function, mitral regurgitation, and other
compensatory or concomitant cardiac abnormalities
needs to be more fully characterized, compared
across THVs and with SAVR, and related to
functional status and outcome. In a similar way,
detection and quantification of P-PM and its frequency and implications is an important and rich
area for future investigation.
Reprint requests and correspondence: Dr. Pamela S.
Douglas, 7022 North Pavilion, Duke University Medical
Center, PO Box 17969, Durham, North Carolina 27715.
E-mail: Pamela.douglas@duke.edu.
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REFERENCES
1. Leon MB, Smith CR, Mack M, et al.
Transcatheter aortic-valve implantation for aortic stenosis in patients who
cannot undergo surgery. N Engl
J Med 2010;363:1597– 607.
2. Smith CR, Leon MB, Mack MJ, et
al. Transcatheter versus surgical
aortic-valve replacement in highrisk patients. N Engl J Med 2011;
364:2187–98.
3. Tamburino C, Capodanno D, Ramondo A, et al. Incidence and predictors of early and late mortality
after transcatheter aortic valve implantation in 663 patients with severe aortic stenosis. Circulation
2011;123:299 –308.
4. Eltchaninoff H, Prat A, Gilard M, et
al. Transcatheter aortic valve implantation: early results of the FRANCE
(FRench Aortic National CoreValve
and Edwards) registry. Eur Heart J
2011;32:191–7.
5. Gurvitch R, Wood DA, Tay EL, et al.
Transcatheter aortic valve implantation:
durability of clinical and hemodynamic
outcomes beyond 3 years in a large
patient cohort. Circulation 2010;122:
1319 –27.
6. Toggweiler S, Leipsic J, Gurvitch R,
et al. Percutaneous aortic valve replacement: vascular outcomes with a
fully percutaneous procedure. J Am
Coll Cardiol 2012;59:113– 8.
7. Kurra V, Schoenhagen P, Roselli EE,
et al. Prevalence of significant peripheral artery disease in patients evaluated
for percutaneous aortic valve insertion:
preprocedural assessment with multidetector computed tomography.
J Thorac Cardiovasc Surg 2009;137:
1258 – 64.
8. Hayashida K, Lefevre T, Chevalier B,
et al. Transfemoral aortic valve implantation: new criteria to predict vascular complications. J Am Coll Cardiol Intv 2011;4:851– 8.
9. Masson J-B, Kovac J, Schuler G, et al.
Transcatheter aortic valve implantation: review of the nature, management, and avoidance of procedural
complications. J Am Coll Cardiol Intv
2009;2:811–20.
10. Joshi SB, Mendoza DD, Steinberg
DH, et al. Ultra-low-dose intraarterial contrast injection for iliofemoral computed tomographic angiography. J Am Coll Cardiol Img 2009;2:
1404 –11.
11. Troianos CA, Hartman GS, Glas KE,
et al. Guidelines for performing ultrasound guided vascular cannulation:
recommendations of the American
Society of Echocardiography and the
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
Society of Cardiovascular Anesthesiologists. J Am Soc Echocardiogr
2011;24:1291–318.
12. Piazza N, de Jaegere P, Schultz C,
Becker AE, Serruys PW, Anderson
RH. Anatomy of the aortic valvar
complex and its implications for transcatheter implantation of the aortic
valve. Circ Cardiovasc Interv 2008;1:
74 – 81.
13. Jayasuriya C, Moss RR, Munt B.
Transcatheter aortic valve implantation in aortic stenosis: the role of
echocardiography. J Am Soc Echocardiogr 2011;24:15–27.
14. Détaint D, Lepage L, Himbert D, et
al. Determinants of significant paravalvular regurgitation after transcatheter aortic valve: implantation impact
of device and annulus discongruence.
J Am Coll Cardiol Intv 2009;2:821–7.
15. Babaliaros VC, Liff D, Chen EP, et
al. Can balloon aortic valvuloplasty
help determine appropriate transcatheter aortic valve size? J Am Coll Cardiol Intv 2008;1:580 – 6.
16. Gurvitch R, Webb J, Yuan R, et al.
Aortic annulus diameter determination by multidetector computed tomography: reproducibility, applicability and implications for transcatheter
aortic valve implantation. J Am Coll
Cardiol Intv 2011;4:1235– 45.
17. Burgstahler C, Kunze M, Löffler C,
Gawaz MP, Hombach V, Merkle N.
Assessment of left ventricular outflow
tract geometry in non-stenotic and
stenotic aortic valves by cardiovascular
magnetic resonance. J Cardiovasc
Magn Reson 2006;8:825–9.
18. Leipsic J, Gurvitch R, Labounty TM,
et al. Multidetector computed tomography in transcatheter aortic valve implantation. J Am Coll Cardiol Img
2011;4:416 –29.
19. Messika-Zeitoun D, Serfaty J-M,
Brochet E, et al. Multimodal assessment of the aortic annulus diameter:
implications for transcatheter aortic
valve implantation. J Am Coll Cardiol
2010;55:186 –94.
20. Delgado V, Ng AC, Shanks M, et al.
Transcatheter aortic valve implantation: role of multimodality cardiac imaging. Expert Rev Cardiovasc Ther
2010;8:113–23.
21. Jilaihawi H, Makkar R, Hussaini A,
Trento A, Kar S. Contemporary application of cardiovascular hemodynamics: transcatheter mitral valve interventions. Cardiol Clin 2011;29:
201–9.
22. Kurra V, Kapadia SR, Tuzcu EM, et al.
Pre-procedural imaging of aortic root
orientation and dimensions: comparison
between X-ray angiographic planar im-
aging and 3-dimensional multidetector
row computed tomography. J Am Coll
Cardiol Intv 2010;3:105–13.
23. Gurvitch R, Wood DA, Leipsic J, et al.
Multislice computed tomography for
prediction of optimal angiographic deployment projections during transcatheter aortic valve implantation. J Am
Coll Cardiol Intv 2010;3:1157– 65.
24. Dvir D, Kornowski R. Real-time 3D
imaging in the cardiac catheterization
laboratory. Future Cardiol 2010;6:
463–71.
25. John M, Liao R, Zheng Y, et al.
System to guide transcatheter aortic
valve implantations based on interventional C-arm CT imaging. Med Image Comput Comput Assist Interv
2010;13:375– 82.
26. Koos R, Mahnken AH, Dohmen G,
et al. Association of aortic valve calcification severity with the degree of
aortic regurgitation after transcatheter
aortic valve implantation. Int J Cardiol
2010;150:142–5.
27. Kapadia SR, Svensson L, Tuzcu EM.
Successful percutaneous management
of left main trunk occlusion during
percutaneous aortic valve replacement.
Catheter Cardiovasc Interv 2009;73:
966 –72.
28. Grube E, Schuler G, Buellesfeld L, et
al. Percutaneous aortic valve replacement for severe aortic stenosis in highrisk patients using the second- and current third-generation self-expanding
CoreValve prosthesis: device success
and 30-day clinical outcome. J Am Coll
Cardiol 2007;50:69 –76.
29. Walther T, Simon P, Dewey T, et al.
Transapical minimally invasive aortic
valve implantation: multicenter experience. Circulation 2007;116:I240 –5.
30. Jilaihawi H, Chin D, Spyt T, et al.
Prosthesis-patient mismatch after transcatheter aortic valve implantation with
the Medtronic-Corevalve bioprosthesis.
Eur Heart J 2010;31:857– 64.
31. Sherif MA, Abdel-Wahab M, Stöcker
B, et al. Anatomic and procedural
predictors of paravalvular aortic regurgitation after implantation of the
Medtronic CoreValve bioprosthesis.
J Am Coll Cardiol 2010;56:1623–9.
32. Piazza N, Nuis R-J, Tzikas A, et al.
Persistent conduction abnormalities
and requirements for pacemaking six
months after transcatheter aortic valve
implantation. EuroIntervention 2010;
6:475– 84.
33. Lerakis S, Babaliaros VC, Block PC,
et al. Transesophageal echocardiography to help position and deploy a
transcatheter heart valve. J Am Coll
Cardiol Img 2010;3:219 –21.
Bloomfield et al.
Practical Guide to TAVR Imaging
JACC: CARDIOVASCULAR IMAGING, VOL. 5, NO. 4, 2012
APRIL 2012:441–55
34. Krishnaswamy A, Tuzcu EM, Kapadia SR. Update on transcatheter aortic
valve implantation. Curr Cardiol Rep
2010;12:393– 403.
35. Tchetche D, Dumonteil N, Sauguet
A, et al. Thirty-day outcome and vascular complications after transarterial
aortic valve implantation using both
Edwards Sapien and Medtronic CoreValve bioprostheses in a mixed population. EuroIntervention 2010;5:
659 – 65.
36. Zoghbi WA, Chambers JB, Dumesnil
JG, et al. Recommendations for evaluation of prosthetic valves with echocardiography and Doppler ultrasound:
a report from the American Society of
Echocardiography’s Guidelines and
Standards Committee and the Task
Force on Prosthetic Valves, developed
in conjunction with the American
College of Cardiology Cardiovascular
Imaging Committee, Cardiac Imaging Committee of the American
Heart Association, the European Association of Echocardiography, the
Japanese Society of Echocardiography
and the Canadian Society of Echocardiography. J Am Soc Echocardiogr
2009;22:975–1014.
37. Sharma UC, Barenbrug P, Pokharel
S, Dassen WRM, Pinto YM, Maessen JG. Systematic review of the outcome of aortic valve replacement in
patients with aortic stenosis. Ann
Thorac Surg 2004;78:90 –5.
38. Gotzmann M, Lindstaedt M, Bojara
W, Mügge A, Germing A. Hemodynamic results and changes in myocardial function after transcatheter aortic
valve implantation. Am Heart J 2010;
159:926 –32.
39. Tzikas A, Geleijnse ML, Van
Mieghem NM, et al. Left ventricular
mass regression one year after transcatheter aortic valve implantation.
Ann Thorac Surg 2011;91:685–91.
40. Tzikas A, Piazza N, van Dalen BM, et
al. Changes in mitral regurgitation
after transcatheter aortic valve implantation. Catheter Cardiovasc Interv
2010;75:43–9.
41. Clavel MA, Webb JG, Rodés-Cabau
J, et al. Comparison between transcatheter and surgical prosthetic valve
implantation in patients with severe
aortic stenosis and reduced left ventricular ejection fraction. Circulation
2010;122:1928 –36.
42. Devereux RB, Alonso DR, Lutas EM,
et al. Echocardiographic assessment of
left ventricular hypertrophy: comparison to necropsy findings. Am J Cardiol 1986;57:450 – 8.
43. Myerson SG, Montgomery HE,
World MJ, Pennell DJ. Left ventricular mass: reliability of M-mode and
2-dimensional echocardiographic formulas. Hypertension 2002;40:673– 8.
44. Buellesfeld L, Gerckens U, Schuler G,
et al. 2-year follow-up of patients
undergoing transcatheter aortic valve
implantation using a self-expanding
valve prosthesis. J Am Coll Cardiol
2011;57:1650 –7.
45. Gotzmann M, Bojara W, Lindstaedt
M, et al. One-year results of transcatheter aortic valve implantation in
severe symptomatic aortic valve stenosis. Am J Cardiol 2011;107:1687–92.
46. Shames S, Koczo A, Hahn R, Jin Z,
Picard MP, Gillam LD. In-stent flow
acceleration in the SAPIEN transcatheter aortic valve: impact on the
echocardiographic assessment of valve
function. J Am Soc Echocardiogr
2011. In press.
47. Clavel M-A, Rodés-Cabau J, Dumont E, et al. Validation and characterization of transcatheter aortic valve
effective orifice area measured by
Doppler echocardiography. J Am Coll
Cardiol Img 2011;4:1053– 62.
48. Ruel M, Rubens FD, Masters RG, et al.
Late incidence and predictors of persistent or recurrent heart failure in patients
with aortic prosthetic valves. J Thorac
Cardiovasc Surg 2004;127:149 –59.
49. Tasca G, Brunelli F, Cirillo M, et al.
Impact of valve prosthesis-patient
mismatch on left ventricular mass
regression following aortic valve replacement. Ann Thorac Surg 2005;
79:505–10.
50. Kohsaka S, Mohan S, Virani S, et al.
Prosthesis-patient mismatch affects
long-term survival after mechanical
valve replacement. J Thorac Cardiovasc Surg 2008;135:1076 – 80.
51. Ewe SH, Muratori M, Delgado V, et al.
Hemodynamic and clinical impact of
prosthesis-patient mismatch after transcatheter aortic valve implantation. J Am
Coll Cardiol 2011:1910 – 8.
52. Clavel M-A, Webb JG, Pibarot P, et
al. Comparison of the hemodynamic
performance of percutaneous and surgical bioprostheses for the treatment
of severe aortic stenosis. J Am Coll
Cardiol 2009;53:1883–91.
53. Abdel-Wahab M, Zahn R, Horack
M, et al. Aortic regurgitation after
transcatheter aortic valve implantation: incidence and early outcome.
Results from the German transcatheter aortic valve interventions registry.
Heart 2011;97:899 –906.
54. Zahn R, Schiele R, Kilkowski C,
Zeymer U. Severe aortic regurgitation
after percutaneous transcatheter aortic
valve implantation: on the importance
to clarify the underlying pathophysiology. Clin Res Cardiol 2010;99:
193–7.
55. Leon MB, Piazza N, Nikolsky E, et
al. Standardized endpoint definitions
for transcatheter aortic valve implantation clinical trials: a consensus report
from the Valve Academic Research
Consortium. J Am Coll Cardiol 2011;
57:253– 69.
56. Block PC. Leaks and the “great ship”
TAVI. Catheter Cardiovasc Interv
2010;75:873– 4.
57. Simpson IA, de Belder MA, Kenny
A, Martin M, Nihoyannopoulos P.
How to quantitate valve regurgitation
by echo Doppler techniques. Br
Heart J 1995;73:1–9.
58. Pouleur A-C, le Polain de Waroux
J-B, Goffinet C, et al. Accuracy of
the flow convergence method for
quantification of aortic regurgitation
in patients with central versus eccentric jets. Am J Cardiol 2008;102:
475– 80.
Key Words: imaging y
multimodality y transcatheter
aortic valve replacement.
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