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112 2—AORTIC VALVE INTERVENTIONS
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Coronary obstruction—This is also a rare complication of balloon-expandable valves. Risk
factors for coronary obstruction include low coronary heights ,11 mm, effacement of the sinuses
with narrow sinotubular junction, bulky leaflets, heavy calcification, and preexisting ostial left
main stent. In situations where the risk of coronary obstruction is high, expectant management
of coronary occlusion can be achieved by placement of a guide catheter, wire, and undeployed
stent in the coronary at risk. If coronary occlusion occurs, the stent can be withdrawn to the ostia
and deployed, keeping the coronary open. If occlusion occurs without the preventive strategy
described here, then all attempts should be made to wire and stent the occlusion; however, this is
usually more difficult to achieve.
Cerebrovascular accident—This occurs in 2% to 6% of patients undergoing TAVR. The
incidence is highest in the periprocedural period. The risk of cerebral embolization is highest
during passage of the valve across the aortic arch, during balloon aortic valvuloplasty, and during
valve deployment. Embolic protection devices have been shown to decrease the incidence of
perfusion abnormalities on magnetic resonance imaging (MRI) but not the incidence of clinical
stroke compared with patients who did not get cerebral embolic protection.
Conduction abnormalities—Development of new left bundle branch block (LBBB) and
complete heart block are more common complications with TAVR, occurring in approximately 20% of cases. Presence of a preexisting right bundle branch block is a predisposing
factor for developing complete heart block. Deployment of the valve in a more aortic position
to avoid interaction with the LVOT helps prevent development of conduction abnormalities.
If complete heart block develops, the temporary pacemaker is left in place, usually via the
right internal jugular vein or subclavian access so as to help with patient mobilization. Development of a new LBBB with a balloon-expandable valve is not an indication to leave a pacemaker in place, but patients need to be monitored closely in case they develop complete heart
block. Other conduction abnormalities include development of advanced atrioventricular
(AV ) block (Mobitz type 1 or 2). These may resolve, remain stable, or progress to complete
heart block. If complete heart block is sustained, permanent pacemaker implantation is performed before discharge.
Aortic regurgitation—In the early TAVR experience, development of significant aortic insuf-
ficiency, usually paravalvular periprosthetic regurgitation, was a major concern. Moderate or
greater aortic paravalvular leak (PVL) has been associated with increased mortality. The use of
computed tomography (CT) sizing and development of new transcatheter heart valves has led to
a reduction in the incidence of significant PVL. If there is significant PVL due to incomplete
expansion of the transcatheter heart valve, balloon postdilation is usually performed with an additional 1 to 2 cc of contrast in the balloon; if the PVL persists and is significant, a second valve
may need to be implanted. In cases of severe central aortic regurgitation, a dysfunctional leaflet
is suspected. This is managed by leaflet manipulation with a pigtail catheter; if there is still severe
central aortic incompetence, a second valve is usually implanted.
Significant PVL may be missed using transthoracic echocardiography (TTE); therefore, in
cases of suspected PVL with a lower-than-normal aortic diastolic pressure, an aortogram should
be performed to rule out significant PVL, or the patient can be intubated and a transesophageal
echocardiography (TEE) probe placed for assessment. In situations where significant PVL is seen
weeks to months post-TAVR, transcatheter PVL closure with the use of Amplatzer devices may
be attempted.
For self-expanding valves, it is important to wait for a full 10 minutes after initial deploy-
ment because the valve does expand gradually and can sometimes seal the PVL. Anything
greater than mild PVL should be treated with postdilatation and, if severe, by placing a second
transcatheter valve in the deployed CoreValve. Excessive LVOT calcification may also lead to
the valve slipping in deeper after release, thereby leading to a PVL that may require placement
of a second valve.
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Pacemaker Requirement After TAVR
Approximately 10% of patients require permanent pacing after TAVR. Patients with preexisting
abnormalities on their electrocardiogram (ECG) are at higher risk of pacemaker requirement
after TAVR. There are no fixed guidelines for pacemaker implantation after TAVR. Patients with
complete heart block, 2:1 block, or other class I indications for pacemaker implantation should
have a pacemaker implanted. Patients with new LBBB after TAVR but with a normal PR interval and heart rate variability usually do not require pacemaker implantation; however, they should
undergo continuous Holter monitoring on discharge to confirm there are no periods of higherdegree heart block.
Acute kidney injury (AKI)—This is a common complication of TAVR. Most TAVR patients
have some degree of renal insufficiency due to age and comorbidities. The risk factors for development of AKI include the presence of preexisting renal dysfunction, hemodynamic instability,
large volume of contrast, and use of nephrotoxic medications.
Summary and Take-Home Messages
n
Complications after TAVR have reduced with improved device design and smaller-caliber
delivery systems.
n
Vascular complications include vessel rupture, stenosis, and dissection. Management of
each complication should be agreed to in advance between the cardiology and vascular
team, dependent on local expertise and availability.
n
Left ventricular perforation and annular rupture are rare complications associated, with a
high mortality. Management is usually surgical.
n
PVLs that are more than mild should be treated with postdilatation at the time of TAVR
if seen on ECG or hemodynamic measurement.
n
Requirement for permanent pacemaker placement remains the most common complication
of TAVR, and newer TAVR devices have been modified in an attempt to reduce this.
CHAPTER 11
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TAVR Alternate Access Sites
Monisha Sudarshan Claire E. Raphael Mayra Guerrero Kevin L. Greason
Background
The transfemoral approach remains the first-line access choice for transcatheter aortic valve replacement (TAVR). Initially up to a third of patients were unsuitable for the transfemoral approach, although this has decreased to less than 10% with contemporary valve designs. In our experience, of
1337 cases (TF 1220, alternative access 117), we used alternative access in just 9% of cases.
Common contraindications to the transfemoral approach include small femoral arterial size,
excess calcification, tortuous arteries, and atherosclerotic disease of the aorta.
When the transfemoral approach is not feasible, an alternative method of arterial access is
needed. Any artery of adequate size can suffice for access, and this includes the left ventricular
(LV ) apex, ascending aorta, carotid artery, axillary artery, iliac artery, and atrial septum.
There is a paucity of comparative literature on alternative access sites, and choice primarily
depends on physician and institutional preference. There is no randomized study comparing
different types of alternative access.
It is important to note that patients undergoing TAVR through alternative access have more
comorbidities and higher rates of coronary and peripheral vascular disease than those suitable for
a transfemoral approach. Unadjusted outcomes suggest higher mortality and complications in the
nontransfemoral group, but after propensity matching for these comorbidities, outcomes are
similar to a transfemoral approach.
protocol and use a safety checklist (Fig. 11.1).
1
As for transfemoral access, it is important to follow a standardized
Transapical
ADVANTAGES, DISADVANTAGES, AND CONTRAINDICATIONS
Unlike the transfemoral approach, transapical access requires general anesthesia and is considered
a more invasive approach. In our experience, the only absolute contraindication to this access is
LV apical thrombus. We have successfully performed transapical access in the presence of severely
reduced ejection fraction, porcelain aorta, mediastinal radiation, and breast implants.
PLANNING
For planning of transapical access, the apex in relation to the chest wall is studied on computed
tomography (CT) scan.
TECHNIQUE
The position of the apex is located using fluoroscopy, and the site is marked on the skin (Fig. 11.2).
The patient is prepped and draped in the supine position. A left anterior thoracotomy incision is
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Has heparin been given and what is the ACT?
Is the pacemaker ready and what is the required rate?
Is the contrast injector ready?
Clinical specialist— what is the valve size?
Is the echocardiography team present and ready?
Is there a pericardial effusion present at baseline?
Fig. 11.1 Mayo Clinic TAVR checklist for intraprocedural pause.
Fig. 11.2 Fluoroscopic identification of the left ventricular apex for incision planning in the trans-
apical approach.
made in the inframammary crease, centered on the LV apex mark. The appropriate rib overlying
the apex is removed in a subperiosteal fashion. The apical fat pad is removed, and the pericardium
is incised to expose the bare area of the LV apex. Both a soft tissue and rigid retractor are helpful
in providing exposure.
Small-caliber sheaths are used to secure percutaneous access in the femoral or radial artery for
insertion of the pigtail catheter in the aortic root and venous access for temporary pacing. Heparin is
administered, with a target activated clotting time (ACT) greater than 250 seconds. Lidocaine is also
administered in preparation for the LV puncture. A balloon-tipped pacing lead is positioned in the
right ventricular apex under fluoroscopic guidance. A standard root angiogram is performed to confirm the prescribed orthogonal angle (“working view”), with the three aortic valve sinuses lined up as
per the methods for transfemoral TAVR.
The systemic blood pressure is lowered to 100 mmHg and kept around that level for the remainder of the invasive part of the procedure, reducing bleeding and allowing hemostasis of the
ventricular puncture site. An anatomically appropriate position for the puncture site can be confirmed
by palpating the proposed site of puncture with a finger and observing the area of indentation on
transesophageal echocardiography.
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Suture placement is one of the most critical aspects of a successful procedure. Full-thickness,
horizontal mattress sutures are placed in the bare area of the LV apex, well away from the left
anterior descending coronary artery (Fig. 11.3). We use pledgetted 2-0 Prolene sutures (Ethicon,
Somerville, NJ) on an MH needle.
The ventricle is punctured and a J-wire positioned across the aortic valve into the ascending
aorta. A 7F sheath is then inserted across the aortic valve. A JR4 catheter is used to position the
J-wire across the aortic arch and down into the lower descending thoracic aorta. The J-wire is
then exchanged for a stiff wire. The JR4 catheter and 7F sheath are then removed. The Edwards
transapical sheath (18F to 21F) is inserted under fluoroscopic guidance. Balloon valvuloplasty
is generally not performed.
The balloon-expandable valve is positioned across the patient’s native aortic valve. Under
rapid ventricular pacing, a root angiogram is completed. The position of the valve is fine-tuned,
and then the valve is deployed in a slow and controlled manner. During deployment, the valve
tends to move ventricularly, and this must be countered with gentle forward pressure on the
delivery device (Fig. 11.4).
After deployment, the delivery device is pulled back into the sheath. Valve position and
function are assessed with intraoperative transesophageal echocardiography. Providing the
valve position and function are satisfactory, the delivery device, wire, and sheath are removed
and the sutures secured.
The pacing lead and pigtail catheter are removed, and protamine is given. The femoral artery
sheath is removed and the site secured with pressure or a closure device. Separate drains are
placed in the pericardial and pleural spaces. The drains are brought out through incisions inferior
to the wound. The pericardium is loosely reapproximated. Because a portion of the rib was
resected, the intercostal space is not brought together. The thoracotomy incision is closed by
approximating the cut edges of the pectoralis muscle.
The pericardial drain is left in place until drainage is less than 30 cc in 24 hours. The pleural
drain can usually be removed when drainage is less than 300 cc in 24 hours.
Fig. 11.3 Transapical access suture placement in the bare area of the left ventricular apex. Ballotting
with the finger under transesophageal echocardiography imaging helps identify the correct spot for suture
placement and apical puncture.
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C
Fig. 11.4 (A) Fluoroscopic image of transapical exposure, transfemoral balloon-tipped pacing lead placement, transfemoral aortic root pigtail placement, and root angiogram. (B) Fluoroscopic image of transapical
transcatheter valve insertion setup just before valve deployment. (C) Fluoroscopic image of successful transapical valve deployment.
APPROACH-SPECIFIC SURGICAL PITFALLS AND COMPLICATIONS
Patients are extubated in the intensive care unit. The systolic blood pressure is carefully
maintained at less than 140 mmHg throughout the postoperative hospital stay.
Transaortic
ADVANTAGES, DISADVANTAGES, AND CONTRAINDICATIONS
Similar to the transapical approach, general anesthesia is required. The image intensifier sits right
over the aortic puncture site and may get in the way during the procedure and increase radiation
exposure to the operators.
Contraindications to this access include significant calcification at the proposed aortic puncture site and a short distance (e.g., less than 6 cm) from the proposed puncture site to the aortic
valve annulus. This is because the introducer sheath requires a minimum length within the body
for successful valve insertion. Previous sternotomy is not a contraindication to transaortic access.
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Thoracotomy Sternotomy
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PLANNING
The position of the aorta in relation to the sternum is determined on CT scan (Fig. 11.5). The key
anatomic landmark is the location of the mid-ascending aorta in relation to a perpendicular line drawn
from the right edge of the sternum (Fig. 11.6). On whichever side of that line the majority of the aorta
lies determines access: that is, .50% of the aorta to the right of the line would be best approached
through a thoracotomy, whereas .50% to the left would be best approached through a sternotomy.
Access is dependent on the underlying anatomy, but is generally through either a limited
right-sided second interspace thoracotomy or upper sternal split/J-type sternotomy.
Fig. 11.5 CT scan at the level of the carina demonstrating the ascending aorta position in reference to a
line drawn perpendicular to the right side of the sternum edge. On whichever side of the line the majority of
the aorta lies determines access (i.e., .50% of the aorta to the right of that line would be best approached
through thoracotomy, whereas .50% to the left would be best approached through a sternotomy).
Fig. 11.6 Direct aortic access through either a limited right-sided second interspace thoracotomy or
upper sternal split/J-type sternotomy.
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TECHNIQUE
The patient is placed in the supine position, with the approach for direct access being either a
limited right-sided second interspace thoracotomy or upper sternal split/J-type sternotomy. In
the right thoracotomy approach, the pectoralis muscle fibers are separated and the pleural space
is entered, with the right internal mammary being ligated and divided. A rib retractor and/or soft
tissue retractor can help expose the ascending aorta. In the case of the upper sternal split/J-type
sternotomy, the pericardium is opened, a pericardial well is made with sutures tied to the skin,
and the retractor is inserted.
Percutaneous access is obtained for the femoral artery and vein, for insertion of a pigtail catheter in the aortic root and a temporary pacing wire. Heparin is administered, with a target ACT
of more than 250 seconds. A standard root angiogram is performed to confirm the prescribed
orthogonal angle to the nadir of the three aortic valve sinuses.
Before incision, fluoroscopy is used to confirm that the proposed site of the aortic puncture is
sufficiently distant from the aortic annulus for sheath insertion. Purse string sutures are placed.
The aorta is punctured and the sheath inserted in the usual stepwise fashion. Balloon valvuloplasty is generally not performed. Valve deployment continues through a set of steps similar to
the standard transfemoral retrograde approach (Fig. 11.7). After successful deployment, the delivery device is removed. Valve position and function are assessed with intraoperative transesophageal
echocardiography.
Once satisfied with adequate valve performance, the sheath is removed and the sutures secured. The pacing lead and pigtail catheter are removed, and protamine is given. The femoral
artery sheath is removed and the site secured with pressure or a closure device.
The pericardial and pleural spaces are drained as needed. No closure of the pericardium is
required. For the right thoracotomy, approximation of the ribs can be attempted to prevent lung
herniation. The J-type sternotomy is closed with usual sternal wire closure.
Approach-Specific Surgical Pitfalls and Complications
Patients are usually extubated in the intensive care unit and managed in a manner similar to that
after surgical aortic valve replacement.
Fig. 11.7 Fluoroscopic image of transaortic setup just before valve deployment.
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Transaxillary
The first published report of a successful transaxillary approach was in 2009,2 and currently the
majority of cases are approached from the left side because the right-sided artery often has a
difficult implantation angle. Because the brachial plexus can weave its way around the delicate
axillary artery, an open surgical exposure of the artery has been used in most cases. However,
percutaneous access has been performed and is emerging as an alternative to traditional surgical
transaxillary access. Data from the TVT registry found that transaxillary/subclavian access was
associated with lower 30-day mortality than transaortic/transapical in a propensity-matched series (5.3% vs. 8.4%, P ,0.01).
transapical approach (6.3% vs. 3.1%, P ,0.05).
ADVANTAGES, DISADVANTAGES, AND CONTRAINDICATIONS
The presence of a patent left internal mammary coronary artery bypass graft needs particular attention.
Although not an absolute contraindication to transaxillary access,
occlude the internal mammary artery. Alternative access routes may be considered in the presence of
a patent left internal mammary artery (LIMA) graft. The presence of an ipsilateral pacemaker can
make surgical preparation more challenging; however, it is not an absolute contraindication.
PLANNING
Subclavian artery stenosis (,6 mm) and/or other significant atherosclerotic disease needs to be
ruled out before the procedure. CT is usually the first-line method, although subclavian angiography can be performed in the cardiac catheterization laboratory. In addition, as discussed later,
any potential LIMA bypass grafts need to be considered (Fig. 11.8).
3
However, the stroke rate was higher compared with a transaortic/
4
there is concern that the sheath may
TECHNIQUE
Access to the artery is obtained through surgical exposure and suturing of an appropriately sized
vascular graft to the mid portion of the axillary artery.
An incision is made overlying the deltopectoral groove approximately 2 cm below the mid-
outer clavicle. The pectoralis major muscle is split along the course of its fibers, and the clavipectoral fascia is divided, exposing the pectoralis minor muscle, which can be retracted away, if
possible, or divided as needed. The location of the axillary artery is variable, and the associated
neurovascular structures must be cautiously handled during attempts to expose the axillary artery
(Fig. 11.9). We prefer to isolate that portion of the axillary artery distal to the thoracoacromial
artery, which supplies blood to the pectoralis major muscle (often used in reconstruction of
complex sternal wounds). Percutaneous access of the artery has also been described.
Percutaneous access is obtained for the femoral artery and vein. Heparin is administered, with
a target ACT of more than 250 seconds. A balloon-tipped pacing lead is inserted through the
femoral venous sheath and positioned in the right ventricular apex. A pigtail catheter is positioned
in the aortic root through the femoral artery sheath. A standard root angiogram is performed to
confirm the prescribed orthogonal angle to the nadir of the three aortic valve sinuses.
After adequate anticoagulation is established, an appropriately sized graft is sutured to the
axillary artery in an end-to-side fashion. The graft is then brought out laterally over the shoulder.
The graft is punctured and a J-wire positioned into the aortic root with use of the JR4 catheter.
The J-wire is then exchanged for a stiff wire and the appropriately sized sheath (typically 14F to
16F) inserted under fluoroscopic guidance. The tip of the sheath is positioned just inside the
ostium of the left subclavian artery. A stable wire access platform is then established across the
aortic valve. Balloon valvuloplasty is generally not performed.
5
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Fig. 11.8 Subclavian and axillary artery anatomy.
Valve deployment continues through a set of steps similar to the standard transfemoral access
approach (Fig. 11.10). After successful deployment, the delivery device is removed. Valve position
and function are assessed with intraoperative transesophageal echocardiography.
Once the valve has been appropriately checked, the graft is removed from the artery and the
defect repaired with a piece of bovine pericardium. The pacing lead and pigtail catheter are removed, and protamine is given. The femoral sheaths are removed and the sites secured with pressure or a closure device. The pectoralis fascia is loosely approximated. The remaining subcutaneous
and skin layers are sutured.
With percutaneous access, closure is usually performed with 2-0 Perclose (Abbott Vascular, CA).
However, there is a risk of bleeding, which in our experience has required covered stent placement.
APPROACH-SPECIFIC SURGICAL PITFALLS AND COMPLICATIONS
The proximity and overlying nature of the brachial plexus on the artery can increase neurologic
complications. Excellent hemostasis is critical due to the limited ability to hold compression,
given the anatomy of the area.
Transcarotid
ADVANTAGES, DISADVANTAGES, AND CONTRAINDICATIONS
The transcarotid approach has emerged as a promising alternative access site. Registry data have
demonstrated high procedural success for both self-expanding and balloon-expandable TAVR in
patients with suitable carotid anatomy. Risk of stroke remains a concern, and contemporary
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