Case Report
Transaxillary Transcatheter Aortic Valve Replacement with a Self-Expanding Valve under Conscious Sedation: Case Discussion and Review of the Literature
Grubb KJ1*, Fields T2, Cheng A1, Settles DM3, Stoddard M4 and Flaherty MP4
1Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine and Jewish Hospital Rudd Heart and Lung Institute, USA
2Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, USA
3Department of Anesthesiology, Cardiac Anesthesiology, Jewish Hospital, USA
4Division of Cardiovascular Medicine, University of Louisville School of Medicine, USA
*Corresponding author: Kendra J. Grubb, Assistant Professor of Surgery, Department of Cardiovascular and Thoracic Surgery, University of Louisville, School of MedicineRudd Heart and Lung Center201 Abraham Flexner Way Suite 1200 Louisville, KY 40202, USA
Published: 30 May, 2016
Cite this article as : Grubb KJ, Fields T, Cheng A, Settles
DM, Stoddard M, Flaherty MP.
Transaxillary Transcatheter Aortic Valve
Replacement with a Self-Expanding
Valve under Conscious Sedation:
Case Discussion and Review of the
Literature. Clin Surg. 2016; 1: 1019.
Abstract
Aortic stenosis is one of the leading causes of structural heart disease in the western world.
Transcatheter aortic valve replacement (TAVR) has become the procedure of choice for patients
deemed high-risk or inoperable for traditional aortic valve replacement and is rapidly proving to be
suitable for lower risk patients. The technology has transformed the management of aortic stenosis.
With growing expertise and more advanced devices, established TAVR programs have adopted a
minimalist approach to TAVR and now routinely perform the transfemoral procedure on patients
with only local anesthetic and monitored anesthesia care (MAC) to facilitate a totally percutaneous
technique. For patients with inadequate iliofemoral access, the risk of vascular injury is extremely
high and alternative techniques have been utilized and include the transapical, transaortic, and
transsubclavian or transaxillary routes. Alternative approaches often require open surgical exposure
under general anesthesia.Herein we describe a unique transaxillary TAVR with a self-expanding
device utilizing only local anesthesia and MAC. To our knowledge, this is the first case in the United
States to describe an awake TAVR with an axillary artery cut down.
Keywords: Transcatheter aortic valve replacement (TAVR); Transcatheter aortic valve implantation (TAVI); Transcatheter heart valve (THV); Transsubclavian; Transaxillary; Minimalist TAVR
Introduction
Transcatheter aortic valve replacement (TAVR) has become the standard of care for high-risk
and inoperable patients with severe symptomatic aortic stenosis (AS) and has shown excellent
outcomes compared to surgery in intermediate risk patients [1-3]. Since the first in man TAVR
in 2002, over 200,000 Transcatheter Heart Valves (THV) have been implanted worldwide with
excellent outcomes [4-7]. In the United States, two THV systems are commercially available, the
balloon expandable Edwards SAPIEN S3 valve (Edwards LifeSciences, Inc., Irvine, California,
USA) (SAPIEN) and the Medtronic CoreValve Revolving System, including the newer EvolutR
(Medtronic CV, Santa Rosa, California, USA) (CoreValve), a self-expanding nitinol frame with a
porcine pericardial valve. Both valve systems have been extensively utilized in the treatment of AS
with excellent outcomes and a significant decrease in mortality compared to medical management
[7-14].
As TAVR centers have gained experience, minimalist approaches (MA) have been employed
whereby the procedure is completed percutaneously on an awake patient, with only local anesthesia
and monitored anesthesia care (MAC) [15-17]. The MA-TAVR has been shown to be safe and
effective and potentially offers cost-savings: the cost for general anesthesia is eliminated, the patient
is mobilized sooner, length of time in the intensive care unit (ICU) is decreased, and discharge is
sooner [15]. The MA-TAVR is most often described from the transfemoral (TF) approach with
a totally percutaneous technique [15,18,19]. However, for TAVR candidates with inadequate
ileofemoral access (<5 mm ileofemoral arteries, sever tortuosity or angulation, and heavy calcium
burden) an alternative approach is necessary to avoid vascular injury [18-20]. It was previously
estimated that one-third of candidates for TAVR have severe
peripheral artery disease necessitations alternative access, however
this number has significantly decreased since smaller delivery systems
are available [21].
Figure 1
Figure 1
Inadequateiliofemoral access. A. Total occlusion of the right iliac and femoral arteries. B & C. Heavily calcified and tortuous left iliac artery with angulation
due to the anastomosis of his transplant kidney as well as a short segment dissection.
Figure 2
Figure 2
Challenging anatomy. D. The left auxiliary artery measured 7.5 mm. E. There was presence of a patent LIMA-LAD bypass graft. F. Heavy calcification of the ascending aorta with patient bypass grafts and a ridge of calcium at the base of the in nominate artery.
Figure 3
Figure 3
The Core Valve system was positioned across the aortic valve annulus at 0 mm ventricular and deployed.
TAs newer devices with smaller delivery systems become available,
alternative access TAVR may become obsolete. However, with the
devices currently available, the SAPIEN S3 (deployed through a
16F, or 18F, inner diameter sheath) and CoreValve (requiring an
18F sheath for a 31mm Valve) necessitate ileofemoral arteries at
least 5.5-7 mm. Alternative access TAVR has been well described
with the transapical (TA) approach being the initial alternative
route for the SAPIEN valve and the transaxillary (TAx), also called
transsubclavian, for CoreValve [9-18,19-22,23]. Both THVs can also
be deployed via a direct transaortic (TAo) approach, a select few
centers have described a transcarotid approach, and early experience
with larger deliver systems even necessitated the use of an iliac
conduit [22,24-27]. Most alternative access routes have required
surgical exposure via a minithoracotomy for TA, auxiliary cut down
for TAx, or ministernotomy for TAo and thus are typically completed
under general anesthesia [18-28].
Herein we present the case of a patient with severe symptomatic
AS, multiple comorbid conditions including pulmonary hypertension,
at extreme-risk for open surgery that had inadequate access for a
MA-TAVR from the TF approach. The patient was treated with a
TAx TAVR with local anesthesia for the auxiliary artery cutdown
facilitated with MAC by a cardiac anesthesiologist. We present this
case as the first case of this kind described in the US.
Case Report
An 80-year-old male presented with worsening symptoms of congestive heart failure (CHF). He was no longer able to complete his activities of daily living and had multiple admissions for exacerbation of CHF (New York Heart Association Class III-IV). His past medical history was significant for polycystic kidney disease resulting in end-stage renal disease for which he had twice undergone renal transplantation, coronary artery disease status post myocardial infarction and coronary artery bypass grafting (with a left internal mammary artery to left anterior descending (LIMA-LAD) and four saphenous vein graft bypasses) as well as repair of the mitral and tricuspid valves, hypertension, hyperlipidemia, peripheral artery disease, tachy-brady syndrome requiring placement of a defibrillator and permanent pacemaker, a history of deep vein thrombosis managed with Coumadin, hyperparathyroidism, obstructive sleep apnea requiring CPAP at night, and paroxysmal atrial fibrillation.
Figure 4
Figure 4
The delivery system was removed and the sheath withdrawn to allow flow into the LIMA, the patency was confirmed with angiography.
During his most recent hospitalization he presented with atypical
chest pain, complaining of worsening fatigue and underwent a full
cardiac evaluation and was found to have patient bypass grafts on
coronary catheterization, pulmonary hypertension (pulmonary
pressure 49/22 mmHg, mean 33 mmHg), and an echocardiogram
revealed left ventricular dysfunction with an ejection fraction of 20-
25%, severe aortic stenosis (aortic valve area 0.7 cm2
, mean gradient 43 mmHg, peak gradient 78.1 mmHg, and velocity across the valve of
442 m/s), as well as aortic insufficiency, moderate mitral regurgitation,
and moderate tricuspid insufficiency. He was medically optimized
and the Heart Valve Team was consulted for evaluation for TAVR.
During TAVR work up he was found to have moderate pulmonary
dysfunction on pulmonary function testing (FEV1: 54% predicted
and DLCO: 43%) and 3 of 4 unsatisfactory frailty metrics (albumin of
3.3, decreased grip strength, and a 15-meter walk of 7.6 seconds). His
Society of Thoracic Surgery (STS) risk of mortality was calculated at
15.3% for open AVR.
A preoperative TAVR CT confirmed a large valve annulus
(diameter 28.5 X 33.9 mm, perimeter 97.9, area 752.7 mm2
).Assessment of his iliofemoral access showed a totally occluded right
iliac and femoral artery, heavily calcified and tortuous left iliac artery
with angulation due to the anastomosis of his transplant kidney and a
short segment dissection (Figure 1). His ascending aorta was heavily
calcified with patient bypass grafts and a ridge of calcium at the base
the innominate artery (Figure 2). The left auxiliary artery measured
7.5 mm. After extensive discussion, TAx TAVR with local anesthesia
and a 31mm CoreValve was deemed the most prudent and viable
option.
The patient was positioned supine and MAC anesthesia with low dose dexmedetomidine was induced for patient comfort. Local
anesthesia was injected in the left infraclavicular region and a 3cm
incision was made parallel to the mid-portion of the left clavicle. The
pectoralis muscle was incised and the exposure was carried down
to the auxiliary vein, well away from the brachial plexus. The vein
was retracted cephalad to expose the axillary artery and vessel loops
were placed proximally and distally. The LIMA was visualized and
the arteriotomy planned medially. Two 4-0 Prolene purse string
sutures were placed in the anterior surface of the auxiliary artery. A
5-F pigtail catheter was advanced to the aortic root via a 6F sheath
placed in the left common femoral artery and a transvenous pacer
was placed through the left common femoral vein. The patient was
systemically heparinized to an ACT of >250 sec. After conformation
of the deployment angle with angiography the left subclavian artery
was cannulated using the Seldinger technique. A long 7F precurved
destination sheath was placed, the aortic valve was crossed, and
a precurved Lunderquist wire was advanced into the ventricle.
The 7F sheath was exchanged for an 18F sheath advanced to the
ascending aorta under direct vision. The Core Valve system was
positioned across the aortic valve annulus at 0 mm ventricular and
deployed (Figure 3). The delivery system was removed and the
sheath withdrawn to allow flow into the LIMA, the patency was
confirmed with angiography (Figure 4) the valve was evaluated with
transesophageal echocardiography and noted to have a mild inferior
paravalvular leak but excellent function.The wire and sheath were
removed and the incision closed in layers.
The postoperative course was unremarkable. He was ambulating
with physical therapy within 8 hours of the operation and transferred
out of the ICU the following morning. Although he was ready for
discharge, at the request of the transplantation service, he was
monitored an additional 24 hours and discharged to home the
morning of the second postoperative day. At 30-day follow up he was
doing well, able to complete all activities of daily living and in NYHA
Class I heart failure.
Discussion
Transcatheter aortic valve replacement has been one of the most
disruptive technologies in the management of cardiovascular disease
in the past ten years. Not only has TAVR allowed for the treatment
of hundreds of thousands of patients once deemed too high-risk
for surgery but the technology has also established a collaborative
approach to heart care.In this case, the Heart Valve Team, including two cardiac
surgeons, an interventional cardiologist, the valve coordinator, an
echocardiologist, and a cardiac anesthesiologist had an extensive
discussion regarding the patient and the case. Although his aortic
valve perimeter was beyond the published range for the CoreValve,
due to heave calcification of the leaflets a seal would likely be possible.
In regard to the access route, initially a TF approach was discussed
but the severe angulation of the proximal left common iliac artery
in conjunction with an additional area of tortuosity at renal artery
anastomosis of his transplanted kidney made the approach risky. The
Team further discussed a TAo approach, but with a questionable site
for cannulation and the need for general anesthesia, this too was a
suboptimal route of access. Alternative access with a TAx approach
seemed the least risky. Employing the routine MA-TF protocol and
avoiding general anesthesia in this patient would be very beneficial.
Alternative access via the TAx approach is well described and has
many advantages over other alternative access options [28-34]. First
described in 2008, the TAx approach became the alternative access
rout of choice for the CoreValve [18,23]. Early experience with TAx
TAVR was summarized by Caceres et al. [35] who highlight high
device success rates and relatively low risk of stroke. Laflamme et
al. [36] published a single-center retrospective study of 174 TAVR
procedures with the CoreValve system, 10% were completed via a TAx
approach under general anesthesia, the authors report the approach is
associated with high procedural success (94%), no stroke or vascular
complications, and no in-hospital or 30-day mortality. Further, they
conclude the TAx approach, due to the shorter distance between the
delivery sheath and the aortic annulus provides better control of the
device and allows more precise positioning [36]. Muenstere et al. [32]
similarly demonstrated the safety of TAx access for a CoreValve in
40 patients and showed no difference in survival between the TF and
TAx groups (p = 0.355) at 30 day, 6-month, and 1-year follow-up
(respectively, 94.1, 77 and 67.4% in the TAx group). Reardon et al.
[18] describe the utilization of alternative access techniques in the
CoreValve Extreme Risk US Pivotal Trial, including 70 patients who
underwent TAVR via a TAx approach; no event of device migration
or embolization occurred, there was no conversion to open surgery,
and the subclavian access resulted in lower 30-day all-cause mortality
rate than TAo access (8.6% vs. 13.7%) but a greater stroke rate (8.6%
vs. 6.5%). A meta-analysis published in 2014 included 1526 patients,
228 with transubclavian access and showed no significant difference
for 30-day mortality (OR 0.64; 95% CI 0.31-1.32; p = 0.23), stroke (OR
0.74; 95% CI 0.27-2.01; p = 0.55), or new pacemaker implantation
(OR 0.88; 95% CI 0.58-1.35; p=0.56) as compared to the TF approach.
However, there was a decreased risk of vascular complications (OR
0.53; 95% CI 0.29-0.95; p=0.03) in the TAx group [17]. Although a
direct comparison between TAx and TA TAVR was not undertaken,
the authors indirectly suggest that TAx may be a better access than TA
for patients without adequate femoral artery access. A report of the
2-year results of CoreValve implantation through the TAx approach
from the Italian CoreValve Registry included 141 TAx patients
matched to TF and found similar outcomes in regard to procedural
success rate (97.9% vs. 96.5%; p = 0.47), major vascular complications
(5.0% vs. 7.8%; p = 0.33), life-threatening bleeding (7.8% vs. 5.7%; p =
0.48), and 2-year freedom from cardiovascular death (87.2 ± 3.1%vs.
88.7 ± 2.8%) [21].
Initially, a patient LIMA-LAD was deemed a contraindication
to TAx TAVR, but many centers have utilized this approach in
previously bypassed patients with low morbidity [31,32-37]. Multiple
case reports have described the case of successful THV implantation
via the left subclavian artery in the presence of a patent LIMA graft
to LAD and suggested this is not an absolute contraindication for
TAx TAVR [37,38]. Modine et al. [31] were the first to publish a
series of patients treated via a TAx approach with patent LIMA-LAD
and proved the technique to be feasible and safe with satisfactory
outcomes. Caution must be taken with the use of this approach in
patients with small caliber subclavian arteries as the 18 F sheath
could be occlusive and result in myocardial ischemia during the THV
deployment [39].
In Europe, the MA-TAVR has transitioned to include the TAx
approach. Cioni et al. [29] described the short- and mid-term results
in an Italian single-center performing the TAx TAVR in the cardiac
catheterization laboratory with local anesthesia and mild sedation:
procedural success rate 96.8%, 30-day mortality 6.4%, and actual
survival at 6 months 82.95%. The authors believe the MA-TAx
approach is a feasible and technically simple TAVR technique. Schafer
et al. [40] described the German totally percutaneous technique
to access the auxiliary artery for TAVR with 37.5% of the patients
undergoing the procedure with local anesthesia and conscious
sedation, however 29% of patients experienced percutaneous closure
failure and required treatment with endovascular stent grafts.
OHerein we have described an alternative access strategy for a
patient with inadequate ileofemoral access in which general anesthesia
could be avoided. We believe the TAx TAVR under local anesthesia
with MAC support is a feasible procedure with low risk. We offer
this case for further discussion and believe this approach should be
added to the armamentarium of US TAVR Teams for the treatment
of challenging cases.
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