Percutaneous treatment of patients with heart diseases: selection, guidance and follow-up. A review
Percutaneous treatment of patients with heart diseases: selection, guidance and follow-up. A review
Carla Contaldi 0
Maria-Angela Losi 0
Antonio Rapacciuolo 0
Maria Prastaro 0
Raffaella Lombardi 0
Valentina Parisi 0
Lucia S Parrella 0
Carlo Di Nardo 0
Alessandra Giamundo 0
Roberto Puglia 0
Giovanni Esposito 0
Federico Piscione 0
Sandro Betocchi 0
0 Department of Clinical Medicine, Cardiovascular and Immunological Sciences, University Federico II , Naples , Italy
Aortic stenosis and mitral regurgitation, patent foramen ovale, interatrial septal defect, atrial fibrillation and perivalvular leak, are now amenable to percutaneous treatment. These percutaneous procedures require the use of Transthoracic (TTE), Transesophageal (TEE) and/or Intracardiac echocardiography (ICE). This paper provides an overview of the different percutaneous interventions, trying to provide a systematic and comprehensive approach for selection, guidance and follow-up of patients undergoing these procedures, illustrating the key role of 2D echocardiography.
Advances in cardiovascular interventional techniques
have allowed percutaneous treatment of conditions that
either previously required open operations or have not
been amenable to any treatment.
Aortic stenosis (AS) is the most common valvular
abnormality in the western world and it is more
frequent in elderly patients with comorbidities.
Transcatheter Aortic Valve Implantation (TAVI) offers an
alternative to patients with severe symptomatic AS and
contraindications for surgery or high risk for surgery .
Mitral regurgitation (MR) has a prevalence of 1-2% in
the general population and there are several percutaneous
techniques for the treatment of it, such as direct
annuloplasty, indirect annuloplasty-coronary sinus and
ventricular remodeling, however only repair by using Mitraclip has
been extensively evaluated . Patent foramen ovale
(PFO) and atrial septal defects (ASD) are interruption of
atrial septum  and their percutaneous closure is a safe
and accepted alternative to surgery [4-7].
Atrial fibrillation (AF) is the most common cardiac
arrhythmias. At present, percutaneous left atrial
appendage (LAA) occlusion may be an acceptable option in
selected high-risk patients with AF who are not
candidates to oral anticoagulation .
Para-valvular leaks (PVLs) represent a complication of
cardiac valve replacement and their surgical repair is
associated with a high mortality and morbidity rate, thus, in
selected cases, percutaneous repair can be performed .
This review emphasizes particularly the role of 2D
echocardiography in selection, guidance and follow up of
patients candidates to percutaneous treatment.
Transcatheter Aortic Valve Implantation TAVI
Diagnosis of AS
The severity of AS is usually assessed by TTE according
to AHA/ACC  and to ESC Guidelines  (Figure 1,
Panel A and B). Low-dose dobutamine echocardiography
can be useful to differentiate between severe and the rare
pseudo severe AS in patients with low LV ejection
fraction and low gradient [10,11].
Indications to TAVI
To date, there is a lack of pharmacological therapies to
prevent the progression of AS and unfortunately, balloon
aortic valvuloplasty has revealed limited long-term efficacy
TAVI can be considered an alternative to surgery
for patients with symptomatic severe AS and with
contraindications or at high risk for surgery (Table 1) .
Patients are defined at high risk for aortic valve
surgery if logistic European System for Cardiac Operative
Risk Evaluation (EuroSCORE)  is > 20% and
Society of Thoracic Surgeons (STS) score  is >
10%. Currently, there are two prosthetic valves for
TAVI: the SAPIEN (Edwards Life Sciences, Inc.) and
the CoreValve (Medtronic, Inc.). Edwards-Sapien valve
consists of three bovine pericardial leaflets, mounted
within a tubular, slotted, stainless steel,
balloonexpandable stent [1,15] and it can be introduced by
transfemoral or transapical approach. The CoreValve
Revalving System has three porcine pericardial leaflets,
mounted in a self-expanding, nitinol frame and it can
be introduced by transfemoral or trans-subclavian
(offlabel use) approach [1,15]. Recently, SAPIEN has
shown to be superior to medical therapy (including
balloon aortic valvuloplasty) [16,17] and to be not
inferior to conventional surgery . Pre-procedural
screening with TTE assesses heart anatomy and
function, and aortic root anatomy. In the first instance it
must be verified that the obstruction to left ventricular
outflow tract (LVOT) is at valvular level and that AS is
severe. The distance from the basal attachment of the non
coronary cusp to the basal attachment of the right
coronary cusp is measured as aortic valve annulus [15,16], in
systole (Table 1). Determining accurate prosthesis size is
critical for device stability to minimize paravalvular aortic
regurgitation (AR) and to prevent aortic rupture .
A gold standard method of annular measurement has
yet to be established . TTE is the primary modality 
for annulus measurement, whereas TEE is performed only
if an accurate measurement cannot be made by TTE ,
or if borderline values lead to doubt the feasibility of the
procedure . This anteroposterior measurement more
closely approximates the minor rather than the major
dimension of the elliptically shaped annulus, as measured
by multidetector computed tomography (CT) .
As current clinical experience and recommendations are
Figure 1 TTE parasternal long axis (Panel A) and TEE
midesophageal long-axis (120-140) view (Panel B) useful to
measure aortic valve annulus and aorto-tubular junction of a
patient with severe AS.
Table 1 Indications to TAVI
CLINICAL CONTRAINDICATIONS ECHOCARDIOGRAPHIC INDICATIONS
Severe AS with Life Expectancy < 1 Year Severe AS Bicuspid Aortic Valve
Symptoms Severe Respiratory Insufficiency for Transapical 18 < Aortic Annulus < 25 Subaortic Stenosis
and Approach mm for SAPIEN Valve; Height of coronary ostia from the base of aortic
High Risk for Previous Surgery of the Left Ventricle using a 20 < Aortic Annulus < 27 valve leaflets < 10 mm
Surgery Patch for Transapical Approach mm for CORE Valve Asymmetric Heavy Aortic Valvular Calcification
Aortic Tubular Junction < 45 Intracardiac Thrombus
mm for CORE Valve Mitral Regurgitation > 2+
Left Ventricular Ejection Fraction < 20%
Severe Left Ventricular Hypertrophy (< 1,7 cm)
Bulky Atherosclerosis of the Ascending Aorta and
Arch for Transfemoral Approach
Calcified Pericardium for Transapical Approach
based on echocardiographic annular measurements,
whereas measurements on CT are generally not routinely
used. Height of coronary ostia from the base of the aortic
valve leaflets need to be 10 mm to prevent coronal
occlusion when the prosthesis is implanted. In presence of
a mitral prosthesis, the prothesis must not be positioned
too low, because it can affect mitral prosthetic function
. Clinical and echocardiographic indications and
contraindications to TAVI are reported in Table 1.
Echocardiography guidance of TAVI
Echocardiography is not mandatory to guide TAVI.
Intraprocedural TEE may play a role with the SAPIEN series in
guiding valve implantation and in early post implantation
assessment . During the transapical approach, TEE is
useful to evaluate MR, can increases because of worsening
LV function, new wall motion abnormalities or
dissyncrony induced by right ventricular pacing. The CoreValve is
generally deployed under fluoroscopic guidance, with TEE
being used on a discretionary basis, whereas post
procedural AR is evaluated by aortography and TTE [1,16].
Device malpositioning can cause severe paraprosthesic
leak that can be managed successfully, in selected cases,
with implantation of a second device inside the primary
prosthesis (Valve-in-Valve procedure) .
Echocardiographic evaluation of TAVI complications and
After TAVI, survival at 30 days is 92.9%, at 1 year it is
78.6% and at 2 years it is 73.7%, so midterm to long-term
survival is encouraging in high-risk patients, although a
substantial proportion of patients died within the first year
. During follow-up, TTE is used to evaluate aortic
valve area, mean gradient and severity and location of AR
(Figure 2, Panel A and B) . During transapical
approach, MR can be induced by a partial deformation of
the mitral annulus. Trans-prosthetic gradients decrease
immediately after successful implantation and remain
unchanged over 12 month follow-up . Non severe
paravalvular AR, that is seen in the immediate
postoperative period, shows improvement in short-term and
midterm follow-up, with only a minority of patients having
moderate AR at follow-up at 6 and 12 months .
Procedural complications and logistic EuroSCORE are strongly
associated with early mortality at 30 days, whereas
comorbidities, such as cerebrovascular disease, chronic kidney
disease and heart failure, and postprocedural paravalvular
AR 2, mainly impact late outcomes between 30 days and
1 year . Valve-in-Valve patients procedural, 30-day
and 12-month outcomes are not different from outcomes
of those who underwent the uneventful procedure .
Percutaneous MR repair with the MitraClip system
Diagnosis of MR
MR can be divided into primary, or organic, and
secondary, or functional categories . Organic MR consists of
myxomatus degenerative disease, with leaflets thickened
and the cords inappropriately long (Figure 3), whereas in
functional MR geometric and/or functional LV change
cordal orientation or apical papillary muscles displacing
inducing a tethering effect on one or on both leaflets 
(Figure 3). The grade of MR is done according to the
guidelines of the American Society of Echocardiography
Indications to MitraClip system
When regurgitation across the valve is the consequence
of inappropriate leaflets coaptation, one surgical
approach is to create a double orifice by suturing the free
edges of the middle leaflet segments, the edge-to-edge, or
Figure 3 TTE apical four chamber views without and with color Doppler show severe Organic MR (Panel A and B) and Functional MR
(Panel C and D).
Alfieri stitch . This technique has now been adapted
for transcatheter use which received Conformit
Europenne mark approval as the MitraClip (Evalve, Inc., Menlo
Park, California) . Indications to intervention with
MitraClip system are derived by the Endovascular Valve
Edge-to-Edge Repair Study (EVEREST)  (Table 2):
patients were selected if they met class I indications for
intervention according to American College of
Cardiology (ACC)/American Heart Association (AHA)
recommendations . To assess indications to percutaneous
correction, measurements are done by TTE, and TEE
(Figure 4) (Table 2). Clinical and echocardiographic
indications and contraindications to percutaneous MR repair
with MitraClip System are reported in Table 2.
Table 2 Indications to MR Treatment by MitraClip System
Left Ventricular EF < 25%
Left Ventricular End-Systolic
Diameter > 55 mm
Mitral Valve Orifice Area < 4 cm2
Figure 4 Scheme of echocardiography measurements to assess
for indication to MitraClip System. Modified by Images courtesy
of Abbott Vascular. (c) 2011.
Echocardiography guidance of percutaneous MR with the
The Clip Delivery System (CDS) has the MitraClip, an
implantable clip, attached to its distal end (Figure 5)
[29,30]. The procedure is performed, with the patient
under general anesthesia, by using fluoroscopy and TEE
and, on occasion, TTE guidance . The first step is
transeptal puncture which requires a crossing of the fossa
ovalis in a posterior trajectory toward the line of mitral
leaflet coaptation, providing adequate superior clearance
above the mitral annular plane. TEE views used for guided
transeptal puncture and positioning are reported in Figure
5. After a perpendicular position with the line of coapta
tion at the middle scallops of the MR origin has been
achieved, the clip is advanced and the clip arms are placed
in the grasping position and pulled back during systole
until the mitral leaflets are captured on the arms of the
clip. Intercommissural view with color Doppler is used to
position the clip perpendicularly to MR origin (Figure 5),
whereas long-axis LV outflow tract view is used to guide
grasping and to evaluate leaflet capture, ensuring both
leaflets are fully inserted into the clip (Figure 5, Panel I). If
leaflet insertion is inadequate, leaflets are released, and
clip repositioned. Before deployment, 4- chamber view
and commissural view with color Doppler are used for
assessment of residual MR and continuous wave Doppler
will exclude mitral stenosis. Color Doppler commissural
and transgastric short-axis views show clip and two mitral
orifices and double-orifice mitral valve with the classic
bow-tie appearance, respectively (Figure 5). If insufficient
improvement in MR is seen after the deployment of one
clip, a second MitraClip can be placed [30,31], by
assessment of the location of the residual MR . After
adequate reduction of MR has been achieved, the clip is
deployed, and the CDS and guide catheter are withdrawn
Echocardiographic evaluation of percutaneous MR with the
MitraClip system Complications and follow-up
In the EVEREST I study, MitraClip had a low incidence of
morbidity and mortality and reduction in MR (less than
2+) was observed in the majority of patients . There
were no cases of clip embolization, whereas partial clip
detachment was seen in 9% of patients; 11% of patients,
with acute procedural success, underwent mitral valve
surgery; within 1 year, 66% of patients had MR 2+,
demonstrating durability of the percutaneous repair .
After percutaneous mitral valve repair, mitral valve area
decreases without evidence of clinically significant mitral
The EVEREST II is the first randomized trial which
compares MitraClip device with open mitral valve surgery.
Although percutaneous repair was less effective in to
reducing MR than conventional surgery, it was associated with
superior safety and similar improvements in clinical
outcomes at 12 months .
TTE follow-up is recommended at 1 and 12 months
Percutaneous closure of PFO and ASD
Diagnosis of PFO
The final step of development of interatrial septum (Figure
6) during fetal life is PFO, functioning as an one way valve;
at birth, PFO closes, however if this step does not occur,
PFO results, and it will open whenever the pressure in the
right exceeds that in the left atrium. Therefore, TTE and
TEE, and transcranial Doppler (TCD) visualize PFO
opening or, performed with contrast, its functional
consequence, the right-to-left shunt (Figure 6, Panel F) [34-36].
Contrast apical 4-chamber view is performed at rest and
during Valsalva maneuver, which is considered to be
adequate in case a bowing of atrial septum towards left atrium
(LA) is visualized (Figure 7) . TTE is considered
positive when, at rest or during Valsalva maneuver, after the
contrast fills the right atrium, 3 microbubbles are seen
in left chambers within three cardiac cycles ; a later
appearance of contrast is usually due to intrapulmonary
shunts . The numbers of bubbles seen in a single still
frame can be used to shunt grading as mild: 3-9 bubbles;
moderate: 10-30 bubbles; severe: 30 bubbles [37,38]
(Figure 7). Contrast TCD is an alternative to contrast TTE
as a screening test, and when positive, i.e. 3 or more
bubbles detected within 20 seconds after the start of injection
 (Figure 8), a TTE is performed for a comprehensive
evaluation of atrial septum such as atrial septal aneurysm
(ASA). ASA is diagnosed by a protrusion of septum into
left or right atrium of > 10 mm or by the sum of
excursions into both atria of > 10 mm with base of 15 mm
 (Figure 7, Panel A). Although TEE is considered the
gold standard , it is usually performed only when a
better PFO anatomic definition is needed .
Figure 5 MitraClip and Echocardiography Guidance of Positioning of MitraClip System. The clip is a wide cobalt/chromium implant with 2
arms (Panel A). TEE views used to guide transeptal puncture are bicaval view (Panel B), for inferior-superior orientation, basal short-axis view
(3060) (Panel C) for anterior-posterior orientation and midesophageal 4-chamber view (Panel D), for assessing height above the valve plane. The
clip is moved to center the origin of the MR jet and axially aligned, by the midesophageal intercommissural view or 2 chambers (60) (Panel E),
and the midesophageal long-axis LV outflow tract view (120-150) (Panel F). Transgastric short-axis view at the mitral leaflet and subvalvular level
(Panel G) is used to rotate the clip to achieve a perpendicular position with the line of coaptation at the middle scallops of the valve at the
origin of the MR. Successively, the clip arms are placed, at about 120, and the mitral leaflets are captured on the arms of the clip. The Color
Doppler midesophageal intercommissural view is used to position the clip perpendiculary to MR origin (Panel H). Midesophageal long-axis LV
outflow tract view is used to guide grasping and to evaluate leaflet capture (Panel I). Transgastric short-axis view demonstrates a double-orifice
mitral valve (Panel L). Images courtesy of Abbott Vascular (c).
Figure 6 Interatrial septal development. The primitive atrium is a single cavity (Panel A) subsequently divided by the septum primum which
grows down from the roof of the atrium, toward the developing endocardial cushions (Panel B). Thus, small perforations begin to develop
superiorly resulting in the ostium secundum (Panel C). The atrial roof grows down along the right side of the septum primum, the septum
secundum, which comes to lie over the ostium secundum, however an opening remains between septa, the PFO (Panel D). At birth, lung
pressures drop and the blood pressure in the left atrium exceeds that of the right atrium, so that the septum primum is shoved against the
septum secundum, obtaining septa fusion (Panel E). If this final step does not occur, PFO results (Panel F).
Indications to percutaneous PFO closure
The prevalence of a PFO has been reported to be 24%
in the general population and increases to 38% in
patients with cryptogenic stroke, suggesting an
association between PFO and stroke . Two prospective
studies in the general population [43,44] indicate that in
healthy people with PFO, embolic events are not more
frequent than in controls, therefore primary prevention
and echocardiographic screening in asymptomatic
patients are not needed . The AHA/ASA and ESO
guidelines recommend antiplatelet agents for secondary
prevention, while patients with hypercoagulable states or
vein thrombosis should be anticoagulated [45-47],
whereas when strokes recur, PFO closure is
recommended; this comes true also for other high-risk
patients, but guidelines leave the definition of high
risk open .
Clinical and echocardiographic indications and
controindications to PFO percutaneous closure are reported
in Table 3 [47-50].
Diagnosis of ASD
ASD is a common form of congenital heart disease
accounting for approximately 10% of all congenital heart
defects . There are four types of ASDs and the only
ASD, at moment, susceptible to percutaneous closure is
the secundum type .
The TTE protocol to imaging ASD is the same
applied during the study of PFO (Figure 9) [3,51].
TTE can evaluate ASD rims although, especially in
adults, TEE is mandatory (Figure 10) . Right
ventricular volume overload indicates that ASD has some
hemodynamic consequences: in the extreme and rare
case, Eisenmengers physiology may result .
Quantification of shunt flow can be accomplished with
calculation of ratio of pulmonary blood flow (Qp) to systemic
blood flow (Qs) , that correlates significantly with
cardiopulmonary functional improvement after
transcatheter ASD closure .
Indications to percutaneous ASD closure
ASD closure is indicated in presence of hemodynamic
significance (Qp/Qs 1,5 and/or right chambers volume
overload) or after a paradoxical embolic event (Table 4)
. Large ASDs (more than 40 mm in diameter), and/or
ASDs with other associated congenital defects, and/or
with inadequate septal rim (< 5 mm) are referred to
surgery [4,5,53]. Clinical and echocardiographic indications
and contraindications to percutaneous ASD closure are
reported in Table 4.
Figure 7 Panel A: interatrial septum bowing towards the right
atrium during normal breathing; Panel B: bowing of the atrial
septum towards the left atrium demonstrating that an
adequate Valsalva manoeuvre has been performed; Panel C:
microbubbles in the left cavities after Valsalva manoeuvre
within three cardiac cycles after the contrast material fills the
right atrium, positive for PFO.
Echocardiography guidance of percutaneous PFO and
During the procedure for PFO, echocardiography is not
usually required, although TEE guidance has been
described extensively in adult patients . ICE has been
proposed as an alternative because does not need either
conscious sedation or general anesthesia . For PFO
and ASD closure, there are a variety of atrial septal
occluder devices. Mostly, devices for PFO closure cover the
atrial septum, whereas devices for ASD closure stent it.
During procedure, the defect is crossed with a curved
catheter and semistiff wire; then, a catheter with balloon
is inflated across the atrial septum until the complete
occlusion of the ASD and absence of shunt is visualized
(Figure 11). The distance between the two notches,
viewed by fluoroscopy, is the diameter stretched of the
defect, corresponding to the diameter of the device
(Figure 11, Panel B). An appropriate diameter device is then
positioned and deployed. Positioning and stability of the
device, elimination of the shunt are evaluated by TEE or
ICE (Figure 11) and fluoroscopy, and, if not satisfactory,
the device can be retrieved at any time [5,9,34].
Echocardiographic evaluation of PFO and ASD closure
complications and follow-up
Percutaneous PFO and ASD closure is a safe and
effective treatment in adults patients, even in case of
thrombophilia or pulmonary hypertension, also during a
longterm follow-up, up to 11 years [6,7]. Early
post-procedure complications, such as pericardial tamponade has
been reported in approximately 0.5% to 1% of patients;
tamponade most frequently results from LAA
perforation during the trans-septal guide wire anchoring .
A early or late post-procedure relatively rare
complication is device embolization . Residual shunts
immediately after device closure of PFO/ASD, are
common and often disappear or decrease, as the device
endothelializes . However, if shunts persist, serial
TTE evaluation must be performed to follow-up the
degree of shunting .
Erosion has been described, as late complication, in
patients with multiple devices, deficient antero-superior
rims and oversizing devices that, also, can cause
superior vena cava occlusion [53,55].
Device thrombosis appears to be more common with
devices containing uncoated metal arms, within the first
month after device implantation . Finally, a late rare
complication is severe mitral valve insufficiency,
probably due to oversized mismatched device traction on the
root of the mitral annulus and mitral annular
insufficient rim .
During follow up, TTE is recommended at 6, 12 and
24 months .
Figure 8 TCD positive for right-to-left shunt after Valsalva
manoeuvre: microbubles overlapping spectrum of Doppler
flow velocity of the middle cerebral artery.
Percutaneous closure of LAA in patients with AF
Echocardiography assessment of LA cavity and LAA in
patients with AF
Patients with AF have an increased risk of
thrombembolic stroke  and in non valvular AF, LAA is the
major site of thrombus formation [58,59].
LAA has a tubular form and is attached by a narrow
junction to the left atrium , it is near to left superior
pulmonary vein and it is closely associated with left
aortic sinus. LAA orifice (ostium) is elliptical and located
between the left ventricle and left superior pulmonary
vein, extending over the atrioventricular groove and the
surface of the left ventricle towards the left circumflex
coronary artery . TEE is the gold standard to
exclude LA and LAA thrombus and to study LAA
anatomic relationship. TEE views usually used to image
LAA are reported in Figure 12. A multiplanar probe
revolving around the cavity (0 to 180) improves the
assessment of its frequently complex structure .
Indications to percutaneous LAA closure
Warfarin is the gold standard treatment to prevent
embolic stroke, but benefits of anticoagulation do not
Table 3 Indications to PFO Closure
Severe Pulmonary Hypertension
Recent Gastrointestinal Bleeding
Controndications to Antiplatelet or
Infection at the Time of Implantation
come without risk of bleeding [62,63] and, moreover, it
is contraindicated in up to 44% of patients with AF .
At present, percutaneous LAA closure is an acceptable
option in selected patients with AF at high-risk of stroke
who are not candidates to oral anticoagulation (Table 5).
In addition, in patients on oral anticoagulation, LAA
occlusion may reduce recurrence of stroke  (Table
Clinical and echocardiographic indications and
contraindications to percutaneous LAA closure are reported in
Echocardiography guidance of percutaneous LAA closure
Independently of the type of device, the actual
deployment methodology is similar. First, standard transeptal
puncture is performed for left atrial access. Next, the
sheath is advanced up to the LAA orifice and a pigtail
catheter is inserted into LAA. Then, TEE and
fluoroscopic evaluate size (length and diameter), shape, and
angulation of the orifice and body of the LAA. The
device is then sized and is advanced into the LAA
Currently, three devices for LAA occlusion have been
specifically designed: the Percutaneous LAA
Transcatheter Occlusion (PLAATO), the WATCHMAN LAA
system and Amplantzer Cardiac Plug Device. The
PLAATO device was the first device, consisting of a
self-expandible nitinol cage covered with a
nonthrombogenic occlusive expanded polytetrafluoroethylene
membrane and currently it is not available because of
economic reasons. The WATCHMAN LAA System
(Atritech, Plymouth, MN) consists of a
parachuteshaped device with a self-expanding nitinol frame
structure with a permeable polyester membrane over the
atrial side and mid-perimeter fixation barbs to secure it
in the LAA; it is permeable to blood, thus patients
require conventional thromboembolic prophylaxis with
6 weeks of warfarin, at which time device
endothelialization is confirmed by TEE . More recently, the
Amplatzer Cardiac Plug (ACP)(AGA Medical) is a
selfexpanding flexible braided nitinol mesh structure
ECHOCARDIOGRAPHIC CONTRAINDICATIONS Other Congenital Heart Defects Eustachian valve and ChiariNetwork
Figure 9 Color flow Doppler shows left to right interatrial shunting at basal parasternal short axis (Panel A), at apical 4- chamber
view (Panel B), and at subcostal 4-chamber view (Panel C).
designed as a distal lobe and a proximal disc linked via a
flexible central waist [66,67]; the lobe of the device is
designed to conform to the inner wall of the LAA with
a depth of 10 mm or more. For this device, TEE at 45,
measures the landing zone from the origin of left
circumflex coronary artery to the roof of LAA, at least 10
mm below the ligament of Marshall (Figure 12, Panel
B). The lobe of the device is anchored in the landing
Figure 10 ASD Rims by TTE and TEE: I. TTE parasternal short axis at level of aortic valve view (Panel A); TEE basal short axis view (Panel B); TTE
apical (Panel C) and subcostal four chamber (Panel D) views; TEE trasversal four chamber view (Panel E); TTE subcostal short-axis view (Panel F)
and TEE long- axis for bicaval veins (Panel G). IA = Inferoanterior; IP = Inferoposterior; P = Posterior; SA = Superoanterior; SP = Superoposterior.
Table 4 Indications to ASD Closure
Severe Pulmonary Hypertension
Recent Gastrointestinal Bleeding
Contraindications to Antiplatelet or
Infection at the Time of Implantation
Figure 11 Sizing of ASD by TEE (Panel A) and by fluoroscopy (Panel B); positioning of the device by TEE basal short axis view (Panel
C) and by ICE long axis view (Panel D).
Figure 12 TEE Image of LAA: horizontal short-axis view at the base of the heart, at 0 (Panel A), and 45 (Panel B), left two-chamber
longitudinal view, at 90 (Panel C) and the view at 135 (Panel D).
Table 5 Indications to LAA Percutaneous Closure
High Risk Patients with AF Not Candidates
for Oral Anticoagulation
Patients with Recurrent Strokes Despite on
CLINICAL ECHOCARDIOGRAPHIC CONTRAINDICATIONS INDICATIONS Recent Surgical Procedure
LAA Depth 10 mm
Active Endocarditis or Bacteriemia
Close Association of LAA with Mitral Valve,
Pulmonary Veins and Circumflex Artery
zone, 1-2 cm distal of the LAA orifice, while the disc
fully covers the orifice of LAA. The size of the device
should be at least 2 mm larger than the diameter of the
LAA landing zone .
TEE is also used to determine any residual flow in the
LAA and to examine device stability . Adequacy of
LAA occlusion can be assessed by contrast injection in
the left atrium and the adequacy device stability by
applying a tug that displaces device by 1 to 2 cm. When
imaging confirms optimal positioning, device is deployed
and delivery system is withdrawn into the right atrium
(Figure 13, ICE is able to provide imaging support
comparable to TEE, including LAA ostial size .
Echocardiographic evaluation of LAA closure
complications and follow-up
To date, LAA percutaneous closure, in particularly with
Amplatzer device, have proved to be a procedure with a
high success rate (96%) and low rate of serious
complications (7%) .
Complications include: ischemic stroke; pericardial
effusions; tamponade; LAA tear/rupture and device
embolization [65,67,69] (Figure 14). To verify the
absence of these complications, a TTE follow up should
be recommended at a day after procedure, at 4 weeks, 3
months and then every 6 months.
Figure 13 EE Guidance of Percutaneous LAA Closure:
evaluation of opening of the device.
Figure 14 TTE view of a LAA Amplantzer device migration in
LA, by apical 4-chambers (Panel A) and 3-chambers (Panel B).
Percutaneous closure of PVLs
Diagnosis of PVLs
PVLs indicates a regurgitation between the prosthetic
ring and the native valvular annulus [70-72] predisposed
by endocarditis, annular calcification and redo operation
for prosthesis malfunction .
TTE is the first diagnostic approach to PVLs (Figure 15)
[70,73]. However, because mechanical mitral valve leaks
produces LA shadowing, the degree of regurgitation is
established by indirect Doppler signs of increased flow
throughout the prosthesis . In prosthesis aortic valve
leaks, because the aortic does not create shadowing in the
LVOT, TTE can estimate both the degree of regurgitation
and the circumferential extent of the regurgitation > 20%
. To select patients for percutaneous treatment TEE is
mandatory: TEE confirms presence, numbers, anatomy
and position of mitral and aortic PVLs. Estimation of size
and shape of the defect  is important in device
Figure 15 Mitral PVL visualized by TTE apical view (Panel A)
and by TEE trasversal four chamber view (0) (Panel B).
selection, taking into account the irregular 3-dimensional
structure of these tunnels . TEE evaluation of mitral
prosthetic valves is done by centering the prosthesis in the
mid-esophageal four-chamber view. Then the sewing ring
is imaged in full by rotation of the imaging plane from 0
to 180, keeping the sewing ring in the center of the image
and making small adjustments of the transducer tip.
Anatomic landmarks for localization of paravalvular leakage
usually used are the aorta and LAA . For aortic
prosthesis, TEE complements TTE mostly in posterior PVLs.
TEE may be limited in evaluating prosthetic AR in the
midesophageal level because of anterior shadowing. In
case of mitral and aortic prosthesis it is critical to evaluate
the aortic one from transgastric view .
Indications to percutaneous PVLs closure
Patients with severe PVLs and/or haemodynamic
instability with symptoms of congestive heart failure or
severe hemolysis are candidates to leak correction
[71,76]. Surgery is the gold standard therapy, though
reoperation is associated with a markedly higher
morbidity and mortality, and higher risk of paravalvular
leakage than the initial procedure [76,77]. In patients
not candidates for surgery, percutaneous closure has
become a feasible option (Table 6) . Clinical and
echocardiographic indications and contraindications to
percutaneous closure are reported in Table 6.
Echocardiographic guidance of PVLs percutaneous
TEE is commonly used for image guidance ; ICE
may represent an alternative, though experience with
TEE is greater . Mitral PVLs can be approached
retrogradely from a catheter in the left ventricle . In
aortic PVLs, the same approach is recommended,
however, it must be carried out very quickly because may
induce prosthetic dysfunction . In the mitral
anterograde approach, a transeptal puncture is performed in
the standard fashion (Figure 16, Panel A) . The
defect of mitral or aortic prostheses is crossed with an
atraumatic guide-wire (Figure 16, Panel B). Sonographer
should attempt to identify a cardiac structure in
proximity to the leak utilized as an initial point of
radiographic reference for the interventionist. Once a
catheter is in the central region of the leak, small
injections of saline, containing sufficient micro-bubbles, are
used to assist in echocardiographic localization of the
catheter tip and to guide manipulation . Wire
passage through the leak can usually be visualized by
echocardiography, and entrapment in ventricular
trabeculations, mitral, or tricuspidal chordate may be
appreciated . The choice of available device is
dependent on the specific size and morphology of the
PVLs as well as on the proximity to prosthetic leaflets.
Table 6 Indications to PVLs Closure
No specific designed devices but umbrella devices,
vascular occluding devices, and coils, have been implanted
. Finally, a closure device is introduced and the
device deployment and positioning may be assessed in
real time (Figure 16, Panel C and D); only when echo
confirms correct positioning, stability, and absence of
interference with normal valve function, the occlusive
device is released [72,76].
Echocardiographic evaluation of PVLs closure
complications and follow-up
PVLs percutaneous closure is a feasible procedure in
selected patients, with a reasonable degree of technical
and clinical success, complete or partial PVL occlusion
in 70% of patients, with concomitant clinical
improvements and an acceptable level of serious complications
Early complications associated with device closure of
PVLs include incomplete closure, impairment of valvular
function, embolization and onset of new haemolysis .
A major limitation of perivalvular leak closure is the
frequent persistence of leak, often due to the semilunar
shape of the defects. In such cases, it may be prudent to
plan a staged procedure, first implanting one device and
after this has fibrosed, deploying another, rather than
risking dislodgement or embolization of the first device with
immediate implantation of a second [76,79]. After the
procedure, hemolysis may develop due to flow through the
device, resolving with time as the device thromboses ,
or because a successful reduction in PVLs size, increases
shear forces across the narrower orifice.
To ensure that device has not migrated, the leak has
been closed follow-up with TTE is generally adequate at
1, 6 and 12 months.
Significant advances in percutaneous repair of many
heart diseases have highlighted the importance of a
systematic approach for selection, guidance and follow up
of patients undergoing these procedures.
Figure 16 TEE evaluation of Mitral PVL Percutaneous Closure: Transeptal puncture (Panel A); mitral prosthesis is crossed with an
atraumatic guide-wire (Panel B); positioning of the device (Panel C) and absence of a residual leak (Panel D).
Echocardiography plays a critical role in patient
selection, particularly in choosing the appropriate size of the
prosthesis to be implanted. To date, TAVI is targeted at
high-risk patients but it may be extended to the lower
risk group in the future, if the initial promise holds true
after careful evaluation.
A combination of TEE and supplemental TTE has been
used for MitraClip procedure. Its safety profile is similar
to other percutaneous procedures and now it is attractive
for high-risk surgical candidates, in future randomized
trial results will define the role for surgical candidates.
Understanding correlation between anatomy and
echocardiography is perhaps the most essential requisite
to ensure a successful PFO/ASD percutaneous closure
procedure. The complication rates for both TEE and
ICE imaging to guide this procedures appear to be low
and acceptable, but ICE should be considered when
suitable expertise is available. LAA percutaneous closure is
an emerging approach and it, with appropriate patient
selection, device iterations, and technical improvements,
may become an important viable therapeutic alternative
to chronic antithrombotic therapy. PVLs percutaneous
closure is a new approach that can be useful for
increasing PVLs because of increasing valve replacements.
Appropriate designed devices for PVLs closure and
improved imaging, particularly with ICE and with a
wide use of 3D TEE, will help in this procedure. The
echocardiography has an important and undeniable role.
For the best result of percutaneous treatment, a close
collaboration between sonographers and interventional
cardiologists is required.
AF: Atrial Fibrillation; AHA/ACC: American Heart Association/American
College of Cardiology; AHA/ASA: American Heart Association/American
Stroke Association; AR: Aortic Regurgitation; AS: Aortic Stenosis; ASA: Atrial
Septal Aneurysm; ASD: Atrial Septal Defects; CDS: Clip Delivery System; CT:
Computed Tomography; ESC: European Society of Cardiology; ESO:
European Stroke Organisation; EuroSCORE: European System for Cardiac
Operative Risk Evaluation; EVEREST: Endovascular Valve Edge-to-Edge Repair
Study; ICE: Intracardiac Echocardiography; LA: Left Atrium; LAA: Left Atrial
Appendage; LV: Left Ventricle; LVOT: Left Ventricular Outflow Tract; MR: Mitral
Regurgitation; PFO: Patent Foramen Ovale; PVLs: Para-Valvular Leaks; Qp:
Pulmonary Blood Flow; Qs: Systemic Blood Flow; STS score: Society of
Thoracic Surgeons Cardiac Operative Risk Evaluation; TAVI: Transcatheter
Aortic Valve Implantation; TCD: Transcranial Doppler; TEE: Transesophageal
Echocardiography; TTE: Transthoracic Echocardiography; Valve in Valve
procedure: percutaneous implantation of a second device inside the primary
percutaneous aortic prosthesis.
C Contaldi drafted the manuscript; MA Losi designed the paper; A
Rapacciuolo, G Esposito, F Piscione, MA Losi and S Betocchi revised it
critically; R Lombardi, V Parisi, M Prastaro, LS Parrella, A Giamundo, C Di
Nardo and R Puglia analyzed data from literature. All authors have read and
approved the manuscript.
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