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102 2—AORTIC VALVE INTERVENTIONS
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8F sheath over a 0.0359 regular J-tipped wire and positioned in the descending aorta. The
regular 0.0359 wire is then exchanged for a stiff 0.0359 wire, which is inserted into the
JR4. Exchanging stiff wires should be done using catheters to avoid injury to the aorta.
The JR4 catheter and the 8F sheath are both removed, and the introducer sheath is then
inserted. The size of the sheath depends on the size of the valve being used. An 18F introducer sheath is needed to insert the 14F CoreValve inline sheath, and a 20F is needed
for the 16F CoreValve inline sheath. The other option would be to start with a 14F or
16F introducer sheath, perform the predilation, and then remove and exchange the 14F
or 16F introducer sheath for the respective 14F or 16F CoreValve inline sheath.
Once the introducer sheath is in position, the stiff wire is again exchanged over a diagnostic catheter to a regular J-tipped wire. Over the J-tipped wire, an AL1 is then advanced to the level of the aortic valve. The regular J-tipped wire is then exchanged for a
0.0359 straight wire, and the aortic valve is crossed by careful probing in a left anterior
oblique (LAO) view. Alternative catheters used for aortic valve crossing include an AL2
if more reach is needed, a multipurpose catheter, and a JR4 catheter. Once the straight
wire is across the aortic valve, the AL1 is advanced into the left ventricle toward the apex
with the tip pointing upward, making sure that it is not entrapped behind the mitral valve
apparatus. The straight wire is then removed, the stiff wire is then advanced into the left
ventricle, and the AL1 is removed. The predilation balloon is then loaded over the stiff
wire and into the introducer sheath, and predilation is then performed.
If predilation is not required, then no introducer sheath is needed; instead, an AL1
catheter is directly inserted into the 8F sheath over a regular 0.0359 wire and positioned
proximal to the aortic valve. The straight wire is then used to cross the aortic valve, advancing the AL1 over it and positioning it in the left ventricle. The straight wire is then
exchanged for a stiff wire, and both the AL1 and the 8F sheath are then removed. This
then allows the CoreValve inline sheath to be introduced over the stiff wire.
6. Before loading the delivery system and before any predilation, inspection of the transcatheter
valve is performed. This is done by viewing the CoreValve using fluoroscopy in an anteroposterior (AP) projection while rotating the system in each direction (Fig. 9.8). This is
important to ensure that no damage has been done during valve delivery system preparation
and to ensure that no gaps or misalignment is present in the valve struts. Particular things
to pay attention to include gaps between the paddle and the pocket, asymmetrical position
of the paddles, or any disruption or loss of parallel alignment of the crown lines.
7. The delivery system is then loaded, and the transcatheter valve system is then delivered
under fluoroscopic guidance across and into the descending aorta. Because the delivery
system catheter shaft is flexible in one plane and not the other, confirm under fluoroscopy
in the distal arch of the aorta that the hat marker (Fig. 9.9) is in view, which then
ensures appropriate orientation of the delivery sheath toward the arch of the aorta. If it is
not in view, rotate the catheter until it is in view.
8. Next, advance the delivery system across the arch of the aorta, keeping a close eye on the
nose cone to ensure that it does not separate from the capsule. This step is done in an
LAO projection.
9. Once the valve is in the aortic sinus, the coplanar angle is set up on fluoroscopy, which is
used to guide advancement and positioning of the CoreValve at the level of the aortic
annulus. It is important to understand that the distance between node 0 and 1 on the
CoreValve frame is 6 mm and the intended depth of the implant is to have the aortic
annulus between 3 and 5 mm.
10. Once the aortic valve is positioned adequately, the fluoroscopic angle is changed to ensure
that the nodes of the CoreValve are viewed as parallel lines and not rings to allow viewing
9—TRANSCATHETER AORTIC VALVE REPLACEMENT USING SELF-EXPANDING VALVE 103
Step 4:
Step 5: Insertion and advancement of
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Device inspection
Nosecone
Node
Paddles
AP
Fig. 9.8 Inspection of the CoreValve under fluoroscopy before loading the delivery system.
delivery system to distal arch of aorta
Correctly loaded capsule
Misload: Paddle out of pocket
and curved capsule
Misload: Bent outflow crown
Misload: Paddle out of pocket
and curves capsule
of the flaring and positioning of the valve during deployment. This is usually done by
adding LAO to the fluoroscopic angle.
11. Rapid pacing up to 120 beats per minute can be instituted if needed at this point. Deploy-
ment of the valve is a two-operator process. The front operator is controlling the depth
of the bioprosthesis by controlling the delivery catheter, and the second operator is turn-
ing the knob of the CoreValve device in a counterclockwise fashion to slowly deploy the
valve (Fig. 9.10). Although the wire can be manipulated to help adjust valve positioning,
our preference is to not manipulate the wire, as that increases the risk of ventricular per-
foration and may also alter the stored tension in the deployment system, thereby increas-
ing the risk of unintended spontaneous movement of the valve.
12. Deployment of the first third of the bioprosthesis is done in a slow fashion by turning the
knob and monitoring under fluoroscopy the flaring of the bioprosthesis and annular
contact. Once there is adequate annular contact, the pressure quickly drops. At this point,
rotation of the knob is then performed quickly until the indicator nears the point of no
recapture and a tactile feedback click is felt and heard. Pressures then rise again at that
point. The valve can be recaptured three times by performing these steps in reverse order.
13. Once two-thirds of the valve is deployed, a transthoracic echocardiogram is used to evaluate
the presence of paravalvular leak and to assess the depth of the bioprosthesis (Fig. 9.11). If
the position is deemed acceptable, releasing the valve is the next step. To perform that safely,
tension in the system should be released first by pushing the delivery system slightly forward
and turning the knob very slowly, releasing each paddle under fluoroscopy. Once the bio-
prosthesis is released, the nose cone is repositioned toward the center of the bioprosthesis
so that it does not attach to the distal frame and disrupt the valve architecture. The valve is
then retracted into the ascending aorta, where the delivery system is closed and locked by
fixing the blue knob and drawing the left gray knob toward the blue, locking the system and
allowing it to be withdrawn into the descending aorta.
104 2—AORTIC VALVE INTERVENTIONS
Step 6: Ensure that the hat of the device is appropriately oriented
Hat
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AP
Correct Incorrect
Step 7: Advance assembly across arch of aorta (LAO) and across aortic valve.
Set up coplanar angles and perform angiography for accurate positioning
With permission from medtronic
4 mm
Target
position
6 mm
Shaft ‘Spines’
Node 2
Node 1
Node 0
Fig. 9.9 Fluroscopy of the delivery system to ensure appropriate delivery sheath orientation.
If postdilation is not required, the stiff wire is exchanged for a regular 0.0359 wire
through the delivery system, which is then withdrawn all the way outside the body and
the Perclose sutures are deployed. However, if postdilation is required and an introducer
sheath is not present, the delivery system is removed over the stiff wire and a 14F or 16F
introducer sheath, depending on the respective inline sheath size used during the procedure, is then placed and a balloon valvuloplasty postdilation is performed.
At the end of the procedure, a transthoracic echocardiogram and, if needed, an aortogram are performed to evaluate the presence of paravalvular leak. Sometimes the size of
the paravalvular leak diminishes after 10 minutes, as the nitinol valve frame continues to
expand as it warms to body temperature.
9—TRANSCATHETER AORTIC VALVE REPLACEMENT USING SELF-EXPANDING VALVE 105
Step 8: Set up deployment
angle to line up the nodes
in parallel and star
countercloc
of the knob and monitor
flar
fluoroscop
Step 9:
of the de
de
is stopped once clic
mar
Step 10: Echocardiographic assessment of
par
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t slow
kwise turning
ing of the valve under
y
Once aortic pressure drops after annular contact
vice, the knob is turned quickly until 2/3 of the
vice is deployed and the pressure rises again. Tu rning
ker is before the point of no recapture.
Fig. 9.10 Slow deployment of the valve while controlling the depth of the prosthesis.
ks are heard and the angiographic
avalvular leak and position Step 11: Device release
Fig. 9.11 Once two-thirds of the valve is deployed, a transthoracic echocardiogram is used to evaluate the presence of paravalvular leak and to assess the depth of the bioprosthesis.
Both paddles seen
106 2—AORTIC VALVE INTERVENTIONS
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Complications
Complications can happen at each step of the procedure:
1. Access-related complications: This includes bleeding (5%)7 and other complications like
dissection, pseudoaneurysm, and fistulas. After Perclose suture deployment, a mild stenosis
at the site of suture deployment is normally seen. However, if the Perclose sutures are
deployed at acute angles, a larger stenosis can be seen, which can lead to claudication.
Avoidance of such complications would require careful access in a vessel that does not have
anterior calcification under fluoroscopic and ultrasound guidance. Carefully placing the
Perclose devices after making a 4- to 5-mm skin incision and spreading the tissue in order
for the Perclose to be advanced safely and deployed is key.
2. Complications related to valve delivery: This includes aortic arch dissections and atheroma
embolization during advancement, especially if there is atheromatous debris, which can
embolize and lead to stroke (close to 2%)
necessary, and if resistance is met, avoidance of pushing against the resistance is important.
3. Complications related to valve deployment: This includes valve embolization, which may
turn into a surgical emergency. Distal embolization into the ascending aorta or limited
valve migration into the ventricle can often occur, which can be treated by correctly positioning a second valve within the malpositioned device. Deeper embolization into the left
ventricle with mitral chordal apparatus interference or distal embolization leading to partial
obstruction of the upper extremity or cerebral vasculature requires emergency surgery.
Although there are anecdotal descriptions of snaring and retrieval of embolized CoreValves, this can more often than not lead to severe vascular injury, as the valve is too large
to be pulled out through access site sheaths. An embolized original nonrepositionable
CoreValve could be retrieved as long as the proximal end was still fully compressed within
the delivery catheter and it was not a sheathless femoral access. Another complication
after deployment is coronary artery obstruction (0.7%).
cedural computed tomography (CT) scan is important to avoid this complication and to
consider coronary protection before valve deployment. This is particularly important in
valve-in-valve procedures. Another deployment-related complication is annular rupture,
which is less of a concern in self-expanding valves unless postdilation is required. This is a
surgical emergency and carries a very high rate of mortality. Another common complication after deployment is the presence of paravalvular leak. More than mild perivalvular leak
should be treated with postdilation and, if severe, by placing a second transcatheter valve
in the deployed CoreValve. In general, it would be important to wait for a full 10 minutes
after initial deployment because the valve does expand gradually and can sometimes seal
the paravalvular leak. Excessive left ventricular outflow tract calcification may also lead to
the valve slipping in deeper after release, thereby leading to a paravalvular leak that may
require placement of a second valve. Lastly, heart block is a concern after self-expanding
valve deployment (10% with the third-generation system
right bundle branch block carries the highest risk for this complication. Calcification on
the anterior or the noncoronary cusp is also a risk factor because of impingement of the
calcium against the His–Purkinje system that courses near the noncoronary cusp.
4. Wire-related complications: The presence of stiff wires in the left ventricle can lead to several
complications, including ventricular laceration and cardiac tamponade, as well as injury to the
mitral apparatus, such as laceration of the papillary muscles or chordae, all of which require
surgical repair. It is important to keep an eye on the wire during the steps of the procedure
to ensure that the wire has not migrated or extend into the apex. During the time of initial
placement, the guidewires should always be unsheathed by gently withdrawing the placement catheter and should not be pushed out of the catheter, especially if resistance is noted.
7
or acute limb ischemia. Careful advancement is
8
Careful evaluation of the prepro-
9
). The presence of a baseline
9—TRANSCATHETER AORTIC VALVE REPLACEMENT USING SELF-EXPANDING VALVE 107
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Key Points
1. TAVR using self-expanding valves is indicated in patients with intermediate, high, or
prohibitive risk for SAVR.
2. Self-expanding valves are potentially useful when there are heavily calcified leaflets, risk of
coronary artery obstruction, failed aortic surgical bioprosthetic valves that are small in diameter, and poor cardiac reserve where rapid pacing would not be tolerated.
3. The outcomes of this procedure using this device have improved parallel to the evolution
of the device design.
References
1. Popma JJ, Adams DH, Reardon MJ, et al. Transcatheter aortic valve replacement using a self-expanding
bioprosthesis in patients with severe aortic stenosis at extreme risk for surgery. J Am Coll Cardiol. 2014;
63(19):1972-1981.
2. Adams DH, et al. Transcatheter aortic-valve replacement with a self-expanding prosthesis. N Engl J Med.
2014;370(19):1790-1798.
3. Reardon MJ, Van Mieghem NM, Popma JJ, et al. Surgical or transcatheter aortic-valve replacement in
intermediate-risk patients. N Engl J Med. 2017;376(14):1321-1331.
4. Kalra SS, et al. Initial experience of a second-generation self-expanding transcatheter aortic valve: the UK
& Ireland Evolut R Implanters’ Registry. JACC Cardiovasc Interv. 2017;10(3):276-282.
5. Manoharan G, Walton AS, Brecker SJ, et al. Treatment of symptomatic severe aortic stenosis with a novel
resheathable supra-annular self-expanding transcatheter aortic valve system. JACC Cardiovasc Interv.
2015;8(10):1359-1367.
6. Popma JJ, Reardon MJ, Khabbaz K, et al. Early clinical outcomes after transcatheter aortic valve replacement using a novel self-expanding bioprosthesis in patients with severe aortic stenosis who are suboptimal
for surgery: results of the Evolut R U.S. Study. JACC Cardiovasc Interv. 2017;10(3):268-275.
7. Holmes DR, Nishimura RA, Grover FL, Jr., et al. Annual outcomes with transcatheter valve therapy: from
the STS/ACC TVT Registry. J Am Coll Cardiol. 2015;66(25):2813-2823.
8. Genereux P, Head SJ, Van Mieghem NM, et al. Clinical outcomes after transcatheter aortic valve replacement using valve academic research consortium definitions: a weighted meta-analysis of 3,519 patients
from 16 studies. J Am Coll Cardiol. 2012;59(25):2317-2326.
9. Thourani VH, Kodali S, Makkar RR, et al. Transcatheter aortic valve replacement versus surgical valve
replacement in intermediate-risk patients: a propensity score analysis. Lancet. 2016;387(10034):2218-2225.
CHAPTER 10
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Transfemoral TAVR Complications
Oluseun Alli Gurpreet Sandhu
Complications
Operators have to be prepared for all emergencies when performing transcatheter aortic valve
replacement (TAVR). Complications should be managed by the team with predefined and discussed protocols, and these will be determined by local expertise. Bailout equipment should be
readily accessible.
Common complications during and after TAVR and how to address them are listed here:
Unexplained hypotension—Look for etiology, start fluids, and add vasoactive medications to
maintain blood pressure (BP). Common causes of hypotension include vascular injury with perforation, retroperitoneal bleed, coronary occlusion, acute severe aortic insufficiency, pericardial
effusion with tamponade, and conduction abnormalities. If hypotension occurs at sheath insertion or removal, suspect peripheral perforation; an early angiography to define iliac anatomy is
essential. If hypotension occurs after passage of the stiff wire into the left ventricle (LV), consider
severe mitral insufficiency and LV perforation, as etiologies and echocardiography are essential to
diagnosis. Consider early cardiopulmonary bypass if not responsive to fluids/vasopressors and
acute cardiac injury is suspected.
Vascular complications—These range from failure of percutaneous closure devices to aortic
rupture. These also include bleeding and other complications like dissection, pseudoaneurysm,
and fistulas. The evolution of TAVR devices with a smaller-caliber access sheath has decreased
the incidence of vascular complications.
After Perclose suture deployment, a mild stenosis at the site of suture deployment is normally
seen. However, if the Perclose sutures are deployed at acute angles, a larger stenosis can be seen,
which can lead to claudication. Avoidance of such complications would require careful access in
a vessel that does not have anterior calcification under fluoroscopic and ultrasound guidance.
Carefully placing the Perclose devices after making a 4- to 5-mm skin incision and spreading the
tissue in order for the Perclose to be advanced safely and deployed are key. This procedure is
described in Chapter 2.
Iliac dissection—Usually seen postprocedure on the completion aortogram. This may manifest as a sluggish flow down the affected iliac artery or complete occlusion of flow. Occasionally,
it may not be flow limiting. If it is non–flow limiting and small, it may be managed conservatively
with no intervention. If there is sluggish flow down the iliac or abrupt occlusion of the iliac,
endovascular intervention is required with angioplasty and stenting. Fig. 10.1 describes management of an iliac dissection with placement of covered stents, with restoration of flow.
Iliac perforation—In contrast to iliac dissection, this is usually marked by hypotension and
hemodynamic instability. Usually, the aortogram reveals extravasation of contrast into the retroperitoneum. Prompt recognition is crucial. Management involves balloon tamponade of the perforation, usually in the iliac artery. Occasionally, an aortic occlusion balloon may need to be placed
in the descending aorta. Once the balloon tamponade is achieved, management of the perforation
will either be via placement of a covered stent to seal the perforation, if feasible, or vascular surgery
108
10—TRANSFEMORAL TAVR COMPLICATIONS 109
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Fig. 10.1 A left iliac dissection with occlusion of flow (left panel, arrowed) managed by endovascular stenting
and restoration of flow (right panel, arrow).
Fig. 10.2 A large right external iliac perforation (left panel, arrows). Manged with endovascular stenting (right
panel, blue arrow) with no major sequelae.
intervention with open repair in the case of extensive perforation or anatomic unsuitability for
covered stent placement (Fig. 10.2).
Vascular thrombosis—This can occur with inadequate anticoagulation or in situations where
the large-bore sheath is left in place for a long period. This is prevented by ensuring adequate
anticoagulation and prompt removal of the large-bore sheath at the completion of the case. If
thrombosis occurs, endovascular management with catheter-directed thrombolysis with or with-
out aspiration thrombectomy may be performed.
Access site occlusion—This can occur when the Perclose suture occludes the common
femoral artery, leading to ischemia of the affected limb. Risk factors include significant plaque/
calcification at the access site and smaller-caliber vessels. Balloon angioplasty to relieve the ob-
struction may be performed; however, occasionally this may require open repair (Fig. 10.3).
Bleeding—Retroperitoneal bleeding occasionally occurs after TAVR. It may be seen on the
contralateral access site or the large-bore sheath site. Measures to avoid retroperitoneal bleeding
involve the use of radial access for the pigtail catheter, use of ultrasound-guided access, and avoid-
ance of a high femoral stick. Supportive measures include reversal of anticoagulation, fluid resus-
citation, transfusions, and use of vasoactive medications as needed.
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Fig. 10.3 A failed perclose with occlusion of the right common femoral artery (left panel, arrowheads); this
was managed by open repair with restoration of flow (right panel, arrow).
Annular rupture—This is a rare but potentially fatal complication of TAVR. It is more common if the valve is inadvertently oversized relative to the aortic annulus and in a heavily calcified
annulus/left ventricular outflow tract (LVOT). It is more common with balloon-expandable
compared with self-expanding valves. Large annular rupture presents as acute hypotension after
valve deployment. Diagnosis is confirmed after injection of contrast through the pigtail, which
may show extravasation of contrast. Immediate echocardiography should be performed, as cardiac
tamponade usually coexists, and preparation for immediate pericardiocentesis should occur. Because the pericardial fluid is frank blood, autotransfusion should be performed if appropriate
circuitry is available. Heparin should be reversed. Management is usually surgical if the patient
can be stabilized sufficiently for bypass to be performed.
Small, contained annular ruptures have been increasingly recognized during TAVR. Some of
these may be sealed by implantation of the TAVR valve. Annular rupture should always be considered if there is pericardial tamponade. Echocardiographic signs of a small contained rupture
include periaortic hematoma and new aortic wall thickening. In the case of a small annular rupture, hemodynamic support, reversal of heparin, and drainage of the pericardial fluid may be
sufficient for a small rupture to seal without surgical intervention.
Cardiac Perforation/LV Rupture
The presence of stiff wires in the LV can lead to several complications, including ventricular
laceration and cardiac tamponade, as well as injury to the mitral apparatus, such as laceration of
the papillary muscles or chordae, all of which require surgical repair. It is important to keep an
eye on the wire during the steps of the procedure to ensure that the wire has not migrated or
extend into the apex. During the time of initial placement, the guidewires should always be unsheathed by gently withdrawing the placement catheter and should not be pushed out of the
catheter, especially if resistance is noted.
LV rupture is usually caused by use of extremely stiff wires for TAVR, such as the Lunderquist
wire. It may also be caused by inadequate shaping and placement of the stiff wire in the LV. LV
perforation usually manifests as acute hypotension. Right ventricle (RV) perforation may result
from placement of the temporary pacemaker wire. There is a higher incidence of RV perforations
with the temporary screw in pacemaker wires, so care must be taken when using this system. This
may present with hypotension/hemodynamic instability or development of pericardial effusion
on echocardiography. Management involves pericardiocentesis and, in some instances, surgical
repair of the perforation.
10—TRANSFEMORAL TAVR COMPLICATIONS 111
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Valve embolization—A rare but recognized complication of TAVR with balloon-expandable
valves. The valve may embolize into the aorta or ventricle. Usually the result of valve malapposition,
undersizing of the prosthesis, inappropriate pacing capture during valve deployment, or poor valve
positioning at deployment (Fig. 10.4). Embolization into the LV confers high mortality and in most
cases requires surgical removal with sternotomy. Aortic embolization can be managed by tracking the
valve into the descending aorta, where it can be deployed with minimal consequences. The valve may
need to be secured by deployment of a large Palmaz-Shatz stent to affix it to the aorta. It is important
to maintain the guidewire across the prosthesis throughout so as to keep the valve from turning and
occluding the aorta. A new valve can then be placed once the embolized valve has been secured in
the descending aorta. An aortogram to rule out a dissection is important once the valve is secure.
Although there are anecdotal descriptions of snaring and retrieval of embolized CoreValves,
this can more often than not lead to severe vascular injury, as the valve is too large to be pulled
out through access site sheaths. An embolized, original, nonrepositionable CoreValve could be
retrieved as long as the proximal end is still fully compressed within the delivery catheter and it
was not a sheathless femoral access.
A
C
Fig. 10.4 Embolization of a balloon-expandable prosthesis. The valve was deployed very low (panels A and
B) and was mainly in the LVOT; attempts to secure it with a second valve failed (panel C) and the first valve
embolized into the left ventricle (panel D).
B
D
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