Keywords
aortic coarctation - aortic valve insufficiency - mitral valve insufficiency - TEVAR
- surgery
Introduction
Coarctation of the aorta (CoA) accounts for 5 to 8% of congenital heart defects and
is typically diagnosed in infancy or childhood. Although rare reports of acquired
CoA exist, the vast majority of cases are congenital. CoA occurs due to failure in
development of the fourth and sixth pharyngeal arches. Bicuspid aortic valve is the
most common cardiac comorbidity seen in association with aortic coarctation.[1]
The clinical presentation of CoA in adulthood varies. The earliest clinical sequela
of untreated CoA is secondary hypertension. Neglected cases can be further complicated
by congestive heart failure, premature coronary artery disease, stroke, aortic dissection,
and sudden death.[2] Unrepaired CoA has a mortality rate approaching 70 to 80% by the fifth decade of
life. Open surgical repair remains the gold standard, either in the form of resection
and end-to-end anastomosis, interposition graft, or subclavian flap aortoplasty.[3] In the last few years, thoracic endovascular aortic repair (TEVAR) has been successfully
reported in carefully selected adult patients with primary or recurrent CoA.[4]
[5]
[6]
We present a unique case of a late diagnosis of CoA presenting with congestive heart
failure associated with severe aortic and mitral valve insufficiency, treated with
staged endovascular repair of the CoA followed by aortic valve replacement and mitral
valve repair.
Case Presentation
A 41-year-old male, with past medical history significant only for hypertension (systolic
blood pressure, 160–180 mm Hg; diastolic blood pressure, 100–120 mm Hg), presented
to the emergency department of our hospital with shortness of breath. Incidentally,
for the past few weeks, the patient had been experiencing new-onset dyspnea. Transesophageal
echocardiogram revealed a bicuspid aortic valve with severe aortic insufficiency,
severe mitral valve regurgitation, and significantly reduced left ventricular ejection
fraction (20%). A computed tomographic angiogram revealed aortic coarctation with
aortic diameter of 7.7 mm at the site of the isthmus ([Fig. 1]). There was a 70 mm Hg gradient at the site of the coarctation.
Fig. 1 Computed tomography angiogram with three-dimensional reconstruction showing coarctation
of the aorta at the site of the isthmus with enlarged left internal mammary artery
(arrow).
It was decided that the patient would benefit from a staged approach, with the coarctation
repaired first, followed by aortic valve surgery a few weeks later. Consideration
was given to simultaneous valve surgery and frozen elephant trunk; however, it was
thought that the significant increase of the cardiopulmonary bypass time would add
considerable morbidity. After obtaining informed consent, the patient underwent successful
endovascular repair of the aortic coarctation with balloon dilatation of the strictured
aorta using a 12 mm × 40 mm standard angioplasty balloon (Boston Scientific, Marlborough,
MA), followed by deployment of a 24 mm × 100 mm covered thoracic aortic graft (Gore,
Newark, DE), followed by trilobe balloon catheter (Gore, Newark, DE; [Fig. 2]). The predilation was done to ensure that the stent graft could be delivered through
the stenotic area as complete as possible expansion of the graft. A 24 mm × 100 mm
TEVAR graft was chosen as the proximal aortic diameter was 17 mm and the distal diameter
was 28 mm. As the purpose of the procedure was elimination of the coarctation, ensuring
a proximal seal and elimination of the gradient was paramount, and allowing the graft
to be unopposed in the aorta distal to the coarctation was acceptable. Extending the
graft distally beyond the area of dilatation could be performed to eliminate the risk
of type IB endoleak, but this would elevate the risk of paraplegia by covering additional
intercostal vessels. Therefore, the shortest available graft was chosen. The graft
was postdilated with the trilobe balloon catheter to ensure expansion of the stent
graft expansion was deemed adequate, thus no balloon postdilation was done to minimize
the risk of aortic rupture. The proximal neck was 2-cm long and the left subclavian
artery was not covered. The final diameter of the stented aorta at the coarctation
site was increased to 18 mm, and there was only a pressure gradient of 10 mm Hg. The
patient was discharged after 2 days on diuretics and enalapril for his congestive
heart failure. Follow-up computed tomography angiogram 3 months later revealed no
endoleak and stable aortic dimensions and graft position. After 3 weeks, the patient
underwent successful double-valve surgery, with triangular resection of the P2 segment
of the posterior leaflet mitral valve and 32-mm semiring annuloplasty (Cosgrove Edwards
(Edwards Lifesciences, Irvine, CA), and replacement of the aortic valve with a 25-mm
On-X mechanical prosthesis (Cryolife, Kennesaw, GA). He was discharged on the fifth
postoperative day with warfarin anticoagulation. Today, 9 months after his surgery,
he is asymptomatic and free of postoperative complications with an ejection fraction
of 40%.
Fig. 2 Postdeployment of a 24 mm × 100 mm thoracic aortic graft (Gore, Newark, DE).
Discussion
CoA typically manifests in infancy with congestive heart failure. Approximately, 15
to 20% of patients remain asymptomatic until adulthood when CoA leads to secondary
arterial hypertension. In this case, the diagnosis was missed until later in life
when the patient presented with congestive heart failure. In addition to the coarctation,
the patient was found to have severe mitral valve regurgitation and severe aortic
insufficiency due to bicuspid aortic valve. To minimize the risk of operative repair,
the decision was made for staged endovascular CoA repair followed by aortic valve
replacement and mitral valve repair.
To the best of our knowledge, this is the first report of TEVAR for CoA followed by
double-valve surgery in an adult with cardiac decompensation. Many approaches have
been used to treat CoA in adults including open surgical repair, balloon angioplasty,
and intravascular self-expanding or balloon-expandable bare-metal stents (BMS).[7]
Several reports have shown that TEVAR is a safe and effective approach to treat primary
and recurrent CoA, as well as complications of prior CoA repair.[4]
[5]
[6] According to multicenter registry analyses, endovascular treatment is performed
using balloon-expandable covered stents in approximately 50% of adult patients with
CoA, stent grafts in 40%, and balloon-expandable uncovered stents in 10% of this particular
patient population.[8]
Advantages of balloon-expandable covered stents include wider commercially available
TEVAR devices in various sizes and lengths that can accommodate different proximal
and distal choice of size, availability of tapered TEVAR grafts to accommodate proximal–distal
aortic diameters and lengths, increased conformability in steep or angulated aortic
arch anatomy, and ability to exclude associated pseudoaneurysm or aneurysm.[4]
[5]
[6] Potential challenges with TEVAR for CoA include inadequate radial force, unnecessary
length of aortic coverage, and the potential difficulties to retrieve the dilator
tip.
Complications occur in approximately 10% of adult patients undergoing TEVAR for CoA.
These include aortic dissection, intraoperative rupture, endoleak, peripheral embolic
episodes, and access site hemorrhage among others. In large series, freedom from reintervention
and observed survival rates at 5 years are 85 and 90%, respectively.[8]
In light of these data, we opted to repair our patient's aortic coarctation with TEVAR.
A few weeks later, successful double-valve surgery was performed. This staged approach
led to excellent postoperative results and the patient remained free of symptoms at
the time of latest follow-up. This unique case provides evidence supporting TEVAR
as a viable method to preoperatively stabilize adults presenting with heart failure
in the setting of CoA and complex valvular disease.
