Keywords
transcatheter aortic valve replacement - carotid stent - aortic stenosis - stroke
Introduction
Transcatheter aortic valve replacement (TAVR) has become the preferred treatment option
for high-risk surgical patients with severe symptomatic aortic stenosis.
In the PARTNER study, major safety concerns have been raised about the neurological
outcome following TAVR.[1] A large meta-analysis over 1,618 TAVR patients showed a 30-day stroke rate of 6.9%.[2] Indeed, the population that develops neurological events tends to have a higher
mortality rate. The principal cause of the neurological events is considered to be
the detachment of aortic debris during catheter manipulation of the calcified valve
as well as cerebral embolization during retrograde aortic arch passage of the device.
Furthermore, a significant supra-aortic disease is frequently associated with the
valvular lesion. Preoperative assessment must be addressed to minimize the risk of
stroke due to supra-aortic trunks disease.
Case
An 84-year-old Caucasian man was referred for severe symptomatic aortic stenosis.
He had a history of hard smoke, coronary artery disease, arterial hypertension, type
II diabetes mellitus, chronic renal failure, permanent atrial fibrillation, and a
previous right carotid artery stenting. The main symptoms were rest dyspnea and recurrent
transient right-side paresthesia and weakness.
The transthoracic echocardiogram showed a low-gradient–low-flow severe aortic stenosis
associated with ischemic dilated cardiomyopathy (ejection fraction of 40%). An ultrasound
scan of the supra-aortic trunks showed patency of the right carotid stent and the
presence of severe contralateral carotid stenosis.
The severity of the stenosis (>80%) according to the North American Symptomatic Carotid
Endarterectomy Trial (NASCET) criteria was confirmed by a cervical computed tomography
scan; the scan also documented several old bilateral ischemic cerebral lesions.
In consideration of the high surgical risk with a “Society of Thoracic Surgeon” risk
score of morbidity or mortality of 32%, we planned a transcatheter approach.
The key question was: Is it safe to perform carotid stenting before TAVR? After Heart
Team discussion, we planned a combined transcatheter procedure. Because of the common
development of bradycardia and hypotension after carotid stenting and raised risk
of asystole in a patient having small aortic orifice area, we performed the aortic
valve replacement first.
Heparin was given to achieve a target activating clotting time of 200 seconds. By
means of a 14-Fr sheath we implanted via a transfemoral access a 23-mm Edwards SAPIEN
S3 bioprosthesis (Edwards Lifesciences; Irvine, California, United States; [Fig. 1]).
Fig. 1 (A and B) Fluoroscopic image of the delivery of the bioprosthesis. (C and D) Intraoperative transesophageal images demonstrating the good result of the implantation.
After hemodynamic normalization, we implanted a 7 × 40 mm Carotid WALLSTENT (Boston
Scientific; Massachussets, United States) in the left carotid artery ([Fig. 2]). The brain was protected by a 3.2-Fr FilterWire EZ (Boston Scientific) device.
The postoperative recovery was uneventful. He is alive and well at 2 years of follow-up.
Fig. 2 Angiographic images of the left carotid axis before (A, yellow arrow) and after (B, red arrow) the stenting.
Discussion
Currently, there is no consensus on the timing, safety, and efficacy of treating concomitant
severe symptomatic aortic and carotid stenosis. Nowadays, in the older population
and in those having multiple comorbidities, a transcatheter approach is an attractive
option.
Owing to the poor prognosis of these untreated conditions, any effort must be achieved
to plan the best treatment in the setting of the multidisciplinary team.
Some authors claim to treat the carotid lesion first, generally 1 month before the
TAVR.[3] The common thought is that the embolic risk is predominantly due to the intrinsic
preexisting carotid disease rather than the aortic manipulation.
By contrast, it is known that stroke rate in asymptomatic patients with a carotid
stenosis of more than 80% range from 3.5 to 5%.[4]
In these situations, the clinical dilemma is that if we address the valve first, most
of the neurological risks still exist due to the embolization of debris from the aortic
arch as well as from the valve and from the diseased carotid artery, especially without
protection device. On the other hand, the risk of hemodynamic depression during ballooning
and deployment of the valve with an impaired cerebral perfusion on the brain side
of the severe stenosis may further increase the procedural risk.
We decided to perform a single combined transcatheter procedure to simultaneously
treat both conditions in a unique intervention. We performed first the TAVR because
we assumed the patient to be at a high risk of hemodynamic instability. And we decided
to simultaneously treat both pathological conditions to manage the symptomatic situations
in a one-stage fashion.
We still need a broader long-term study on this cohort of patients to effectively
evaluate the feasibility and security of this single-stage procedure.