REVIEW
Heart, Lung and Circulation (2015) 24, 110–118 1443-9506/04/$36.00 http://dx.doi.org/10.1016/j.hlc.2014.08.006
Hypoplasia, Pseudocoarctation and Coarctation of the Aorta – A Systematic Review Sujata Singh, MBBS a, Fayaz A. Hakim, MD b, Ashwini Sharma, MD b, R. Raina Roy, MD b, Prasad M. Panse, MD d, Krishnaswamy Chandrasekaran, MD b, Jorge R. Alegria, MD c, Farouk Mookadam, MSc, FRCPC, FACC b* a
Division of Hospital Internal Medicine, Mayo Clinic, Scottsdale, USA Division of Cardiovascular Diseasey, Mayo Clinic, Scottsdale, USA c Division of Diagnostic Radiology, Mayo Clinic, Scottsdale, USA d Division of Cardiovascular Diseases, Sanger Heart & Vascular Institute-Charlotte-Blythe, Charlotte, USA b
Received 12 March 2014; received in revised form 23 June 2014; accepted 11 August 2014; online published-ahead-of-print 23 August 2014
Aortic arch abnormalities are uncommon and may be seen in association with other congenital cardiac anomalies. Coarctation, pseudocoarctation and hypoplastic aortic arch are known aortic arch abnormalities, with the former being well studied, whilst for the latter two, much less is known. There are similarities and differences that are important to distinguish among these three conditions in order to avoid errors in diagnosis that may result in unnecessary investigations, which may in turn result in physical or emotional harm to the patient. For this reason, we present a systematic review of the published literature providing an evidence-based overview that may be helpful to clinicians when faced with this diagnostic dilemma. Keywords
Aorta Coarctation Hypoplastic arch Pseudocoarctation Congenital heart disease
Introduction The incidence of congenital heart disease (CHD) including even trivial lesions is approximately 75-81/1000 live births while the incidence of CHD requiring postnatal expert management is 2.5-3.0/1000 live births [1,2]. There have been important advances in the diagnosis and management of CHD in last few decades. The availability of sophisticated imaging technology has enabled accurate diagnosis of congenital cardiac anomalies in the prenatal period through to adulthood. Congenital anomalies of the aortic arch occur due to mal-development and involution of the six pairs of arches that arise from the paired dorsal aortae [3]. Development of the aorta is complex and occurs during the third week of
gestation. The primitive aorta has ventral and dorsal segments. The ventral aorta fuses to form the aortic sac while the dorsal aorta joins to form the descending aorta. Subsequently, the six pairs of aortic arches develop further, connecting the aortic sac to the dorsal segment. During the fourth week of embryologic development of the heart, pharyngeal arches receive arteries from the heart. The cardiovascular system results from the development, fusion or regression of these six pairs of arteries coursing through the pharyngeal arches. Arches I, II and V regress, arch III forms the carotid system, and arch IV forms the aortic arch on the left and subclavian artery on the right. Arch VI forms both the pulmonary arteries and the ductus arteriosus on the left. These developmental milestones coupled with increased blood
Abbreviations: CHD, congenital heart disease; CT, computerised tomography; JVP, jugular venous pressure; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging; TEE, transoesophageal echocardiography; TTE, transthoracic echocardiogram; VSD, ventricular septal defect *Corresponding author at: Farouk Mookadam, MSc, FRCPC, FACC, Mayo Clinic, 13400 East Shea Boulevard, Scottsdale, AZ 85259. Tel.: +480-301-6907; fax: +480-301-8018, Email: [email protected] © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier Inc. All rights reserved.
111
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
flow through the aorta at six weeks of gestation are responsible for the development of a normal aortic arch. An anomalous development or insufficient increase in blood flow through the aorta can lead to a variety of aortic arch abnormalities that are frequently associated with other types of CHD [4]. Coarctation of the aorta is a well known and studied congenital condition, which is typified by a narrowing of the descending aorta typically located at the aortic isthmus or the insertion site of the ductus arteriosus distal to origin of left subclavian artery. Aortic coarctation comprises 6-8% of CHD with an incidence of 4/10,000 live births [1,2]. It has a male preponderance and is frequently associated with other cardiac anomalies such as a bicuspid aortic valve, transposition of the great arteries, ventricular septal defect and patent ductus arteriosus. Hypoplastic aortic arch and pseudocoarctation of the aorta are two lesser known aortic anomalies that may be mistaken for the better known lesion of coarctation. This misdiagnosis may lead to unnecessary anxiety for the patient and their families, while adding cost and possible harm from unnecessary invasive investigations. Hypoplastic arch is mostly seen in the paediatric age group and has rarely been reported as an isolated finding. Hypoplastic aortic arch may be seen in as many as 81% of patients with coarctation of the aorta [5] or may occur in association with other congenital anomalies such as tetralogy of Fallot [6], ventricular septal defect [7], and pulmonary artery sling [8]. Both coarctation and hypoplastic aortic arch are thought to be part of the same disease spectrum with pathological association between the coarctation and tubular hypoplasia of the transverse arch. Both conditions may cause hypertension proximal to the obstruction; other symptoms and haemodynamic findings will depend on the presence of effective collateral circulation around the obstructed aortic segment. The third anomaly, pseudocoarctation of the aorta, consists of an elongated arch with a kink at the level of the isthmus. It does not cause obstruction to blood flow but can be associated with other congenital anomalies, including coarctation of aorta [9]. The diagnosis of these three anomalies can raise confusion due to their overlapping and similar clinical, radiological and pathophysiological features. This leads to unnecessary noninvasive or invasive investigations which may be costly, provoke anxiety, or pose risk to the patient. We present cases of hypoplastic arch and pseudo-coarctation of the aorta and compare and contrast these with true coarctation by reviewing the clinical presentation, imaging modalities and management of these three conditions.
Methods We searched PubMed, Medline, EMBASE and Scopus using the terms ‘‘pseudocoarctation of the aorta,’’ ‘‘hypoplastic arch,’’ ‘‘tubular aortic arch,’’ and ‘‘aorta.’’ The search was repeated by a qualified librarian using the same search engines and terms. For pseudocoarctation, cases were selected for inclusion if they met the following criteria:
English language, adult human patients, published in the last 20 years, true congenital form of pseudocoarctation (not pseudocoarctation ‘‘like’’ picture due to other causes such as aortic sarcoma and postoperative constriction), and included a description of clinical presentation and management of the patients. For hypoplastic arch we used the same inclusion criteria other than the age group. We included all cases, adult and paediatric, in the search strategy for hypoplastic arch cases due to the paucity of adult published data.
Findings The search strategy resulted in 312 articles for pseudocoarctation and hypoplastic arch. After discarding studies and case reports that involved neonates and paediatric population (for pseudocoarctation) and articles addressing only surgical techniques, a total of 21 cases of pseudocoarctation and hypoplastic arch (18 pseudocoarctation including one case presented here and three hypoplastic arch cases) were included in this review. Articles were analysed for patient demographics, clinical symptoms and radiological studies. The findings are summarised in Table 1.
Hypoplastic Arch Illustrative Case 1 A 22 year-old man presented to the outpatient cardiology clinic for a routine visit. The patient had a known history of a bicuspid aortic valve and coarctation of aorta diagnosed at four years of age. A peak gradient of 20 mmHg across the aortic valve and a 35-mm gradient across the aortic coarctation were measured at that time. The patient was under regular surveillance with no hypertension and was physically active without functional limitations. On examination, he had a normal carotid pulses and jugular venous pressure (JVP) and waveforms. Sitting blood pressures recorded were: left upper extremity 122/80, right upper extremity 158/70, left lower extremity 150/100 and right lower extremity 150/ 100 mmHg. The brachial pulses were asymmetrical (right stronger than the left) and a brachiofemoral delay was noted on the right side. The femoral, dorsalis pedis and tibial pulses were reduced on both lower limbs. Cardiac examination revealed a systolic click, a grade 2/6 ejection systolic murmur, and a high-pitched diastolic murmur at the left upper sternal border. The systolic murmur was loudest in the suprasternal area. A chest radiograph was unremarkable. Transoesophageal echocardiography (TEE) demonstrated a bicuspid aortic valve with mild to moderate aortic regurgitation. The ascending aorta was hypoplastic with acute angulation of the aortic arch. Colour Doppler showed flow acceleration across the transverse arch. Mean Doppler gradient across aortic valve was 10 mmHg and in the descending aorta 16 mmHg. A nonobstructive web in the proximal descending thoracic aorta distal to dilated left subclavian artery was seen.
Case #
112
Table 1
Demographics, Presentation, Imaging Results and Treatment/Outcome in 20 Cases of Pseudocoarctation of Aorta.
Author
Age/Sex
Clinical Presentation
CXR
Echo
Known coarctation of
NA
NA
CT Scan
MRI
Cardiac Catheterisation
Treatment
Elongated aortic arch
NA
No gradient across
Observation
[Reference] 1
Bolen MA [14]
49/M
aorta
with kink at isthmus; no
isthmus
collaterals 2
Ezhilan J [18]
36/M
Hypertension
NA
NA
Pseudocoarctation of
NA
aorta 3
Etemad-Rezai R [20]
68/M
Back and chest pain
NA
NA
Pseudocoarctation of
No gradient across coarct
NA
segment NA
NA
Observation
Aortic dissection
NA
Surgical repair with good
aorta 4
Mazzola A [21]
52/ M
Right arm hypertension;
NA
BAV
NA
chronic aortic dissection
with false lumen
(type B)
compressing the true
outcome
lumen causing pseudocoarctation 5
Tung R [15]
23/M
Dyspnoea, syncope; equal
NA
BP all 4 extremities
BAV with severe AI;
NA
Tapered descending aorta
NA
MVP with severe MR
Surgery (Bentall procedure) and MV repair
6
7
Amico A [19]
Choi BW [22]
64/M
40/F
Refractory hypertension;
Widening of superior
Dilated ascending
Pseudocoarctation with
reduced femoral pulses;
mediastinum and double
thoracic aorta, BAV
severe stenosis of vessel
murmur in LPSA
AA
Normal examination
Mediastinal mass due to
(including BP and pulse)
dilated aorta
Sudden onset back pain
NA
NA
NA
kinked aorta with end to
lumen NA
NA
Surgical excision of end anastomosis
Elongated & helical aortic
NA
Observation
arch with multiple saccular aneurysms
8
Shindo S [17]
44/M
NA
Kinking and stenosis in
NA
NA
the distal aortic arch with
Emergent surgery for impending rupture
a distal aneurysm 9
Joseph M [23]
49/F
Refractory hypertension;
NA
weak femoral pulses
Complex mass in lumen
Calcified descending
Intramural haematoma at
of the descending aorta
aorta; intraluminal mass
the thoracic level causing
interposition of a tube
pseudocoarctation
graft with resolution of
with 145 mmHg gradient
NA
Surgical excision with
hypertension 10
11
Woolfson PI [24]
Gay WA [23]
36/F
63/F
Known coarctation,
Aortic arch at the level of
Left sided ectatic aortic
Ectatic aorta with a
Surgical repair with AVR
presenting with
T2 and marked
arch
gradient of 100 mmHg
and MVR 2 years F/U
hypertension
narrowing NA
Refractory hypertension;
High aortic arch
NA
hyperlipidaemia; CVA;
Severe AR, MR
Gradient across thoracic
Calcified thickening of
10 cm long narrowing on
Takayasu’s. Percutaneous
aorta
the wall of the
thoracic aorta with
angioplasty and stenting
descending aorta with
130 mmHg gradient
with better BP control
morbidly obese
coarctation at the level of diaphragm 12
Ikonomidis JS [25]
23/M
Chest & abdominal pain;
Left pleural effusion
NA
labile blood pressure
Tortuous arch and
NA
NA
corkscrew proximal
Removal of mediastinal haematoma due to rupture of aorta between the cervical arch and
Grigsby JL [26]
49/M
Dizziness; systolic murmur at equal pulses
Aneurysm of AA
Aneurysm of the aortic
Tortuous brachiocephalic
arch. Pseudocoarctation
vessels
with 11 mmHg gradient
NA
Mild AS echo aortic area
Surgical resection of
to be 1.1 cm 2 with a
aneurysm wand AVR
mean gradient of 22 mmHg.
S. Singh et al.
pseudocoarctation 13
Case #
Author
Age/Sex
Clinical Presentation
63/F
Chest pain; hypertension
CXR
Echo
CT Scan
MRI
Cardiac Catheterisation
Treatment
Widened superior
NA
Mediastinal mass seen on
High aortic arch with
NA
NA
x-ray
kinking at the ligament
[Reference] 14
Soler R [27]
mediastinum
arteriosum 15
Wann LS [16]
74/M
Hypertension, dyspnoea,
Widened mediastinum
Moderate AI; dilated AA
NA
Dilated AA and DA
NA
Surgical repair
Hypertension; BP
Left superior mediastinal
NA
Vascular mass in relation
Tortuosity & buckling of
Normal
NA
discrepancy in upper
mass
with aorta
the aortic arch
Dilatation of the aortic
NA
NA
Surgical repair
Mass adjacent to the
Kinking without
Kinked aortic segment
Observation
aortic arch
narrowing of the thoracic
without a gradient
murmur of AI 16
Munjal AK [28]
22/M
extremities 17
Kessler RM [29]
NA
Dysphagia
Superior mediastinal
NA
mass
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
Table 1. (continued).
aneurysm below the level of the pseudo coarctation
18
Shibata T [30]
43/F
ESM heard at LLSB
Mass above the aortic
NA
knob and rib notching seen
aorta at the junction of the arch and DA
19
Tsai LM [31]
24/M
Right arm HTN; systolic
Upper mediastinum
murmur
mass; rib notching
Dyspnoea on exertion;
Left mediastinal mass
Discontinuous aortic arch
NA
NA
Kinked aortic arch
Surgical repair with resolution of hypertension
20
Connolly JP [32]
36/M
NA
Normal
NA
labile BP; abnormal CXR
Arch aortogram; no
NA
gradient across the kinked segment
21
Klein LW [33]
55/F
Short stature; cardiac murmur; CHF
Prominent aortic knob
BAV and AI
NA
NA
Severe AI; 60%
Medical therapy
constriction of DA but no pressure gradient
Abbreviations AA = ascending aorta; AR = aortic regurgitation; AS = aortic stenosis; AVR = aortic valve replacement; BAV = bicuspid aortic valve; BP = blood pressure; CVA = cardiovascular accident; CXR = chest x-ray; CHF = congestive heart failure; DA = descending aorta; HTN = hypertension; LLSB = left lower sternal border; MR = mitral regurgitation; MV = mitral valve; MVP = mitral valve prolapse; MVR = mitral valve replacement; NA = not applicable.
113
114
Figure 1 Magnetic resonance angiogram showing hypoplastic arch, stenotic segment (presumed coarctation) and post stenotic dilatation of the aorta.
S. Singh et al.
The left ventricular wall thickness was increased with normal size and function. Cardiac magnetic resonance angiography (MRA) showed a bicuspid valve, hypoplastic aortic arch, a stenosis (presumed aortic coarctation) distal to the left subclavian artery with post-stenotic dilatation and collateral flow (Figure 1). Flow acceleration across the arch suggesting a gradient across the transverse arch was present. The sinus of Valsalva measured 2.5 cm, the sinotubular junction 2.0 cm, and the maximum dimension of the ascending aorta was 2.1 cm. The diameter of the coarctation segment was 1.7 cm and that of aorta distal to the coarctation 2.3 cm. Cardiac catheterisation showed normal right and left heart pressures. The mean aortic valve gradient was 12 mmHg and peak systolic gradient from ascending to descending aorta was 6 mmHg. There was no gradient between the aortic arch and the descending aorta indicating that the small gradient in the descending aorta was solely due to the hypoplasia of the ascending aorta. Rotational angiography demonstrated hypoplasia of the aortic arch; distal ascending aorta measured 16 mm, descending limb of the arch 21 mm, and the area of ‘‘presumed coarctation’’ 19 mm suggesting a diagnosis of pseudocoarctation rather than a true coarctation (Figure 2). Due to clear angiographic evidence of a hypoplastic arch
Figure 2 Aortogram obtained at the time of cardiac catheterisation showing aortic dimensions at various levels.
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
together with lack of a significant gradient, no intervention was done. At four month follow-up, his blood pressure was well controlled at rest and during exercise while on amlodipine 10 mg and lisinopril 40 mg daily.
Discussion The aortic arch is said to be hypoplastic if the ratio of the ascending aorta to transverse arch is less than 0.5 [4]. The haemodynamic molding theory suggests that a reduction in foetal blood flow causes hypoplasia and coarctation of the aortic arch. Twenty-five to 50% of infants diagnosed with coarctation have hypoplasia of the arch without haemodynamically significant narrowing and/or pressure gradient across the narrowed segment. Surgical management in such patients is only required for associated cardiac anomalies [10]. This condition is usually seen in the paediatric population and is rarely encountered in adults as seen in the case presented. Patients who presented in their teens had significant fatigue and exhaustion as presenting complaints and were found to have physical findings of coarctation. A computerised tomography (CT) angiogram confirmed the diagnosis in all the three identified cases demonstrating not only hypoplastic arch but also associated cardiovascular anomalies.
115
We have summarised the patients with hypoplastic aortic arch in Table 1. Two of the three patients were female with a mean age of 10.75 years at diagnosis. Two patients had associated coarctation of the aorta and one had a ventricular septal defect (VSD). A systolic murmur at the left upper sternal border is a common physical finding. Hypoplastic arch may be associated with subclavian steal syndrome and can present with exertional headache, asymmetrical upper extremity pulses and a systolic murmur in the left second intercostal space. Pulmonary artery aneurysm was reported in one patient with associated VSD complicated by pulmonary hypertension. Chest radiography was normal in two patients and a prominent aortic knuckle was reported in the third case. Computerised tomography and echocardiography demonstrated a hypoplastic arch and associated congenital anomalies. Patients who underwent cardiac catheterisation were found to have a gradient across the hypoplastic segment. All the three patients underwent open thoracotomy and either a graft placement or reconstruction of the aorta. Surgical repair or reconstruction of the hypoplastic segment has been recommended in symptomatic patients with hypoplastic aortic arch. The type of surgical repair depends on the age of the patient, imaging findings, and operative findings.
Figure 3 Computed Tomography angiogram (A) and volume rendering imaging (B) showing pseudocoarctation of aorta.
116
S. Singh et al.
Pseudocoarctation Illustrative Case 2 A 49 year-old gentleman presented with a week-long history of left sided sharp chest pain radiating to the back and worse with inspiration. At age 26, he was diagnosed with testicular cancer that was successfully treated with orchiectomy and radiation. Physical examination revealed a normal JVP, peripheral pulses, and blood pressures in both upper and lower extremities. Auscultation of the heart revealed a 2/6 early diastolic murmur best heard at the left lower sternal border. Transthoracic echocardiogram (TTE) showed a trileaflet aortic valve with an abnormal anterior cusp resembling
healed endocarditis. Transoesophageal echocardiography (TEE) showed moderate aortic insufficiency with leaflet margins thickening which impaired cooptation. Computerised tomographic angiogram of the chest showed pseudocoarctation of the aorta (Figure 3). The patient was prescribed a short course of non-steroidal anti-inflammatory medication for musculoskletal symptoms with good resolution. Annual follow up with echocardiogram and endocarditis prophylaxis was recommended.
Discussion Pseudocoarctation of the aorta is a congenital anomaly occurring when embryonic compression of the third through
Table 2 Comparing coarctation, pseudocoarctation and hypoplastic arch. Coarctation CLINICAL FEATURES
Pseudocoarctation
Hypoplastic Arch
Male > female
Male > female, average age diagnosed
Hypertension in the upper
43 years.
Shortness of breath, fatigue,
extremities, brachialfemoral delay, and low or
Hypertension. Unequal BP in extremities may or may not be
weakness, syncope, exertional headache,
unobtainable arterial blood
present. Dyspnoea, dysphagia and
hypertension.
pressure in the lower
chest pain or back pain suggests
Systolic murmur in 2nd left
extremities.
complications. Patient may also be
intercostal space. Absent or
Continuous cardiac
completely asymptomatic.
unequal pulse, asymmetric
murmurs present due to
Various cardiac murmurs heard along
blood pressure in
collateral flow. Mid systolic
the sternal borders, base of neck or
extremities.
murmur in interscapular area due to flow across the
interscapular region, along with those of associated cardiac abnormalities.
narrowing.
Associated with vein of Galen
Associated with Turner’s
malformation, Turner’s.
syndrome CHEST X-RAY
Notching in posterior third
Widening of superior mediastinum
Normal sized heart with
of 3rd to 8th ribs, usually
and double aortic arch.
prominent aortic knob.
apparent between ages of
High aortic arch. Superior mediastinal
4-12. Sign of 3 on
mass.
oesophagogram due to preand post-coarct dilation. ECHOCARDIOGRAM
CT/MRA
CARDIAC CATHETERISATION
Narrowing within the
Dilation and kinking in proximal
Hypoplastic arch with
lumen of the proximal
descending aorta. Discontinuity of the
coarctation.
descending thoracic aorta.
arch.
Abnormal flow in collateral
Aneurysm below the level of
vessels seen on colour flow and Doppler.
pseudocoarctation.
Location and severity of the
Kinked and elongated arch, tapered
Hypoplastic arch.
coarctation, collaterals and
descending aorta and corkscrew
Associated cardiovascular
associated cardiac
appearing segment of aorta. May also
defects.
abnormalities.
show aneurysmal dilations.
Gradient across the narrow
No or
Heart, Lung and Circulation (2015) 24, 110–118 1443-9506/04/$36.00 http://dx.doi.org/10.1016/j.hlc.2014.08.006
Hypoplasia, Pseudocoarctation and Coarctation of the Aorta – A Systematic Review Sujata Singh, MBBS a, Fayaz A. Hakim, MD b, Ashwini Sharma, MD b, R. Raina Roy, MD b, Prasad M. Panse, MD d, Krishnaswamy Chandrasekaran, MD b, Jorge R. Alegria, MD c, Farouk Mookadam, MSc, FRCPC, FACC b* a
Division of Hospital Internal Medicine, Mayo Clinic, Scottsdale, USA Division of Cardiovascular Diseasey, Mayo Clinic, Scottsdale, USA c Division of Diagnostic Radiology, Mayo Clinic, Scottsdale, USA d Division of Cardiovascular Diseases, Sanger Heart & Vascular Institute-Charlotte-Blythe, Charlotte, USA b
Received 12 March 2014; received in revised form 23 June 2014; accepted 11 August 2014; online published-ahead-of-print 23 August 2014
Aortic arch abnormalities are uncommon and may be seen in association with other congenital cardiac anomalies. Coarctation, pseudocoarctation and hypoplastic aortic arch are known aortic arch abnormalities, with the former being well studied, whilst for the latter two, much less is known. There are similarities and differences that are important to distinguish among these three conditions in order to avoid errors in diagnosis that may result in unnecessary investigations, which may in turn result in physical or emotional harm to the patient. For this reason, we present a systematic review of the published literature providing an evidence-based overview that may be helpful to clinicians when faced with this diagnostic dilemma. Keywords
Aorta Coarctation Hypoplastic arch Pseudocoarctation Congenital heart disease
Introduction The incidence of congenital heart disease (CHD) including even trivial lesions is approximately 75-81/1000 live births while the incidence of CHD requiring postnatal expert management is 2.5-3.0/1000 live births [1,2]. There have been important advances in the diagnosis and management of CHD in last few decades. The availability of sophisticated imaging technology has enabled accurate diagnosis of congenital cardiac anomalies in the prenatal period through to adulthood. Congenital anomalies of the aortic arch occur due to mal-development and involution of the six pairs of arches that arise from the paired dorsal aortae [3]. Development of the aorta is complex and occurs during the third week of
gestation. The primitive aorta has ventral and dorsal segments. The ventral aorta fuses to form the aortic sac while the dorsal aorta joins to form the descending aorta. Subsequently, the six pairs of aortic arches develop further, connecting the aortic sac to the dorsal segment. During the fourth week of embryologic development of the heart, pharyngeal arches receive arteries from the heart. The cardiovascular system results from the development, fusion or regression of these six pairs of arteries coursing through the pharyngeal arches. Arches I, II and V regress, arch III forms the carotid system, and arch IV forms the aortic arch on the left and subclavian artery on the right. Arch VI forms both the pulmonary arteries and the ductus arteriosus on the left. These developmental milestones coupled with increased blood
Abbreviations: CHD, congenital heart disease; CT, computerised tomography; JVP, jugular venous pressure; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging; TEE, transoesophageal echocardiography; TTE, transthoracic echocardiogram; VSD, ventricular septal defect *Corresponding author at: Farouk Mookadam, MSc, FRCPC, FACC, Mayo Clinic, 13400 East Shea Boulevard, Scottsdale, AZ 85259. Tel.: +480-301-6907; fax: +480-301-8018, Email: [email protected] © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier Inc. All rights reserved.
111
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
flow through the aorta at six weeks of gestation are responsible for the development of a normal aortic arch. An anomalous development or insufficient increase in blood flow through the aorta can lead to a variety of aortic arch abnormalities that are frequently associated with other types of CHD [4]. Coarctation of the aorta is a well known and studied congenital condition, which is typified by a narrowing of the descending aorta typically located at the aortic isthmus or the insertion site of the ductus arteriosus distal to origin of left subclavian artery. Aortic coarctation comprises 6-8% of CHD with an incidence of 4/10,000 live births [1,2]. It has a male preponderance and is frequently associated with other cardiac anomalies such as a bicuspid aortic valve, transposition of the great arteries, ventricular septal defect and patent ductus arteriosus. Hypoplastic aortic arch and pseudocoarctation of the aorta are two lesser known aortic anomalies that may be mistaken for the better known lesion of coarctation. This misdiagnosis may lead to unnecessary anxiety for the patient and their families, while adding cost and possible harm from unnecessary invasive investigations. Hypoplastic arch is mostly seen in the paediatric age group and has rarely been reported as an isolated finding. Hypoplastic aortic arch may be seen in as many as 81% of patients with coarctation of the aorta [5] or may occur in association with other congenital anomalies such as tetralogy of Fallot [6], ventricular septal defect [7], and pulmonary artery sling [8]. Both coarctation and hypoplastic aortic arch are thought to be part of the same disease spectrum with pathological association between the coarctation and tubular hypoplasia of the transverse arch. Both conditions may cause hypertension proximal to the obstruction; other symptoms and haemodynamic findings will depend on the presence of effective collateral circulation around the obstructed aortic segment. The third anomaly, pseudocoarctation of the aorta, consists of an elongated arch with a kink at the level of the isthmus. It does not cause obstruction to blood flow but can be associated with other congenital anomalies, including coarctation of aorta [9]. The diagnosis of these three anomalies can raise confusion due to their overlapping and similar clinical, radiological and pathophysiological features. This leads to unnecessary noninvasive or invasive investigations which may be costly, provoke anxiety, or pose risk to the patient. We present cases of hypoplastic arch and pseudo-coarctation of the aorta and compare and contrast these with true coarctation by reviewing the clinical presentation, imaging modalities and management of these three conditions.
Methods We searched PubMed, Medline, EMBASE and Scopus using the terms ‘‘pseudocoarctation of the aorta,’’ ‘‘hypoplastic arch,’’ ‘‘tubular aortic arch,’’ and ‘‘aorta.’’ The search was repeated by a qualified librarian using the same search engines and terms. For pseudocoarctation, cases were selected for inclusion if they met the following criteria:
English language, adult human patients, published in the last 20 years, true congenital form of pseudocoarctation (not pseudocoarctation ‘‘like’’ picture due to other causes such as aortic sarcoma and postoperative constriction), and included a description of clinical presentation and management of the patients. For hypoplastic arch we used the same inclusion criteria other than the age group. We included all cases, adult and paediatric, in the search strategy for hypoplastic arch cases due to the paucity of adult published data.
Findings The search strategy resulted in 312 articles for pseudocoarctation and hypoplastic arch. After discarding studies and case reports that involved neonates and paediatric population (for pseudocoarctation) and articles addressing only surgical techniques, a total of 21 cases of pseudocoarctation and hypoplastic arch (18 pseudocoarctation including one case presented here and three hypoplastic arch cases) were included in this review. Articles were analysed for patient demographics, clinical symptoms and radiological studies. The findings are summarised in Table 1.
Hypoplastic Arch Illustrative Case 1 A 22 year-old man presented to the outpatient cardiology clinic for a routine visit. The patient had a known history of a bicuspid aortic valve and coarctation of aorta diagnosed at four years of age. A peak gradient of 20 mmHg across the aortic valve and a 35-mm gradient across the aortic coarctation were measured at that time. The patient was under regular surveillance with no hypertension and was physically active without functional limitations. On examination, he had a normal carotid pulses and jugular venous pressure (JVP) and waveforms. Sitting blood pressures recorded were: left upper extremity 122/80, right upper extremity 158/70, left lower extremity 150/100 and right lower extremity 150/ 100 mmHg. The brachial pulses were asymmetrical (right stronger than the left) and a brachiofemoral delay was noted on the right side. The femoral, dorsalis pedis and tibial pulses were reduced on both lower limbs. Cardiac examination revealed a systolic click, a grade 2/6 ejection systolic murmur, and a high-pitched diastolic murmur at the left upper sternal border. The systolic murmur was loudest in the suprasternal area. A chest radiograph was unremarkable. Transoesophageal echocardiography (TEE) demonstrated a bicuspid aortic valve with mild to moderate aortic regurgitation. The ascending aorta was hypoplastic with acute angulation of the aortic arch. Colour Doppler showed flow acceleration across the transverse arch. Mean Doppler gradient across aortic valve was 10 mmHg and in the descending aorta 16 mmHg. A nonobstructive web in the proximal descending thoracic aorta distal to dilated left subclavian artery was seen.
Case #
112
Table 1
Demographics, Presentation, Imaging Results and Treatment/Outcome in 20 Cases of Pseudocoarctation of Aorta.
Author
Age/Sex
Clinical Presentation
CXR
Echo
Known coarctation of
NA
NA
CT Scan
MRI
Cardiac Catheterisation
Treatment
Elongated aortic arch
NA
No gradient across
Observation
[Reference] 1
Bolen MA [14]
49/M
aorta
with kink at isthmus; no
isthmus
collaterals 2
Ezhilan J [18]
36/M
Hypertension
NA
NA
Pseudocoarctation of
NA
aorta 3
Etemad-Rezai R [20]
68/M
Back and chest pain
NA
NA
Pseudocoarctation of
No gradient across coarct
NA
segment NA
NA
Observation
Aortic dissection
NA
Surgical repair with good
aorta 4
Mazzola A [21]
52/ M
Right arm hypertension;
NA
BAV
NA
chronic aortic dissection
with false lumen
(type B)
compressing the true
outcome
lumen causing pseudocoarctation 5
Tung R [15]
23/M
Dyspnoea, syncope; equal
NA
BP all 4 extremities
BAV with severe AI;
NA
Tapered descending aorta
NA
MVP with severe MR
Surgery (Bentall procedure) and MV repair
6
7
Amico A [19]
Choi BW [22]
64/M
40/F
Refractory hypertension;
Widening of superior
Dilated ascending
Pseudocoarctation with
reduced femoral pulses;
mediastinum and double
thoracic aorta, BAV
severe stenosis of vessel
murmur in LPSA
AA
Normal examination
Mediastinal mass due to
(including BP and pulse)
dilated aorta
Sudden onset back pain
NA
NA
NA
kinked aorta with end to
lumen NA
NA
Surgical excision of end anastomosis
Elongated & helical aortic
NA
Observation
arch with multiple saccular aneurysms
8
Shindo S [17]
44/M
NA
Kinking and stenosis in
NA
NA
the distal aortic arch with
Emergent surgery for impending rupture
a distal aneurysm 9
Joseph M [23]
49/F
Refractory hypertension;
NA
weak femoral pulses
Complex mass in lumen
Calcified descending
Intramural haematoma at
of the descending aorta
aorta; intraluminal mass
the thoracic level causing
interposition of a tube
pseudocoarctation
graft with resolution of
with 145 mmHg gradient
NA
Surgical excision with
hypertension 10
11
Woolfson PI [24]
Gay WA [23]
36/F
63/F
Known coarctation,
Aortic arch at the level of
Left sided ectatic aortic
Ectatic aorta with a
Surgical repair with AVR
presenting with
T2 and marked
arch
gradient of 100 mmHg
and MVR 2 years F/U
hypertension
narrowing NA
Refractory hypertension;
High aortic arch
NA
hyperlipidaemia; CVA;
Severe AR, MR
Gradient across thoracic
Calcified thickening of
10 cm long narrowing on
Takayasu’s. Percutaneous
aorta
the wall of the
thoracic aorta with
angioplasty and stenting
descending aorta with
130 mmHg gradient
with better BP control
morbidly obese
coarctation at the level of diaphragm 12
Ikonomidis JS [25]
23/M
Chest & abdominal pain;
Left pleural effusion
NA
labile blood pressure
Tortuous arch and
NA
NA
corkscrew proximal
Removal of mediastinal haematoma due to rupture of aorta between the cervical arch and
Grigsby JL [26]
49/M
Dizziness; systolic murmur at equal pulses
Aneurysm of AA
Aneurysm of the aortic
Tortuous brachiocephalic
arch. Pseudocoarctation
vessels
with 11 mmHg gradient
NA
Mild AS echo aortic area
Surgical resection of
to be 1.1 cm 2 with a
aneurysm wand AVR
mean gradient of 22 mmHg.
S. Singh et al.
pseudocoarctation 13
Case #
Author
Age/Sex
Clinical Presentation
63/F
Chest pain; hypertension
CXR
Echo
CT Scan
MRI
Cardiac Catheterisation
Treatment
Widened superior
NA
Mediastinal mass seen on
High aortic arch with
NA
NA
x-ray
kinking at the ligament
[Reference] 14
Soler R [27]
mediastinum
arteriosum 15
Wann LS [16]
74/M
Hypertension, dyspnoea,
Widened mediastinum
Moderate AI; dilated AA
NA
Dilated AA and DA
NA
Surgical repair
Hypertension; BP
Left superior mediastinal
NA
Vascular mass in relation
Tortuosity & buckling of
Normal
NA
discrepancy in upper
mass
with aorta
the aortic arch
Dilatation of the aortic
NA
NA
Surgical repair
Mass adjacent to the
Kinking without
Kinked aortic segment
Observation
aortic arch
narrowing of the thoracic
without a gradient
murmur of AI 16
Munjal AK [28]
22/M
extremities 17
Kessler RM [29]
NA
Dysphagia
Superior mediastinal
NA
mass
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
Table 1. (continued).
aneurysm below the level of the pseudo coarctation
18
Shibata T [30]
43/F
ESM heard at LLSB
Mass above the aortic
NA
knob and rib notching seen
aorta at the junction of the arch and DA
19
Tsai LM [31]
24/M
Right arm HTN; systolic
Upper mediastinum
murmur
mass; rib notching
Dyspnoea on exertion;
Left mediastinal mass
Discontinuous aortic arch
NA
NA
Kinked aortic arch
Surgical repair with resolution of hypertension
20
Connolly JP [32]
36/M
NA
Normal
NA
labile BP; abnormal CXR
Arch aortogram; no
NA
gradient across the kinked segment
21
Klein LW [33]
55/F
Short stature; cardiac murmur; CHF
Prominent aortic knob
BAV and AI
NA
NA
Severe AI; 60%
Medical therapy
constriction of DA but no pressure gradient
Abbreviations AA = ascending aorta; AR = aortic regurgitation; AS = aortic stenosis; AVR = aortic valve replacement; BAV = bicuspid aortic valve; BP = blood pressure; CVA = cardiovascular accident; CXR = chest x-ray; CHF = congestive heart failure; DA = descending aorta; HTN = hypertension; LLSB = left lower sternal border; MR = mitral regurgitation; MV = mitral valve; MVP = mitral valve prolapse; MVR = mitral valve replacement; NA = not applicable.
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114
Figure 1 Magnetic resonance angiogram showing hypoplastic arch, stenotic segment (presumed coarctation) and post stenotic dilatation of the aorta.
S. Singh et al.
The left ventricular wall thickness was increased with normal size and function. Cardiac magnetic resonance angiography (MRA) showed a bicuspid valve, hypoplastic aortic arch, a stenosis (presumed aortic coarctation) distal to the left subclavian artery with post-stenotic dilatation and collateral flow (Figure 1). Flow acceleration across the arch suggesting a gradient across the transverse arch was present. The sinus of Valsalva measured 2.5 cm, the sinotubular junction 2.0 cm, and the maximum dimension of the ascending aorta was 2.1 cm. The diameter of the coarctation segment was 1.7 cm and that of aorta distal to the coarctation 2.3 cm. Cardiac catheterisation showed normal right and left heart pressures. The mean aortic valve gradient was 12 mmHg and peak systolic gradient from ascending to descending aorta was 6 mmHg. There was no gradient between the aortic arch and the descending aorta indicating that the small gradient in the descending aorta was solely due to the hypoplasia of the ascending aorta. Rotational angiography demonstrated hypoplasia of the aortic arch; distal ascending aorta measured 16 mm, descending limb of the arch 21 mm, and the area of ‘‘presumed coarctation’’ 19 mm suggesting a diagnosis of pseudocoarctation rather than a true coarctation (Figure 2). Due to clear angiographic evidence of a hypoplastic arch
Figure 2 Aortogram obtained at the time of cardiac catheterisation showing aortic dimensions at various levels.
Hypoplasia, Pseudocoarctation and Coarctation of Aorta
together with lack of a significant gradient, no intervention was done. At four month follow-up, his blood pressure was well controlled at rest and during exercise while on amlodipine 10 mg and lisinopril 40 mg daily.
Discussion The aortic arch is said to be hypoplastic if the ratio of the ascending aorta to transverse arch is less than 0.5 [4]. The haemodynamic molding theory suggests that a reduction in foetal blood flow causes hypoplasia and coarctation of the aortic arch. Twenty-five to 50% of infants diagnosed with coarctation have hypoplasia of the arch without haemodynamically significant narrowing and/or pressure gradient across the narrowed segment. Surgical management in such patients is only required for associated cardiac anomalies [10]. This condition is usually seen in the paediatric population and is rarely encountered in adults as seen in the case presented. Patients who presented in their teens had significant fatigue and exhaustion as presenting complaints and were found to have physical findings of coarctation. A computerised tomography (CT) angiogram confirmed the diagnosis in all the three identified cases demonstrating not only hypoplastic arch but also associated cardiovascular anomalies.
115
We have summarised the patients with hypoplastic aortic arch in Table 1. Two of the three patients were female with a mean age of 10.75 years at diagnosis. Two patients had associated coarctation of the aorta and one had a ventricular septal defect (VSD). A systolic murmur at the left upper sternal border is a common physical finding. Hypoplastic arch may be associated with subclavian steal syndrome and can present with exertional headache, asymmetrical upper extremity pulses and a systolic murmur in the left second intercostal space. Pulmonary artery aneurysm was reported in one patient with associated VSD complicated by pulmonary hypertension. Chest radiography was normal in two patients and a prominent aortic knuckle was reported in the third case. Computerised tomography and echocardiography demonstrated a hypoplastic arch and associated congenital anomalies. Patients who underwent cardiac catheterisation were found to have a gradient across the hypoplastic segment. All the three patients underwent open thoracotomy and either a graft placement or reconstruction of the aorta. Surgical repair or reconstruction of the hypoplastic segment has been recommended in symptomatic patients with hypoplastic aortic arch. The type of surgical repair depends on the age of the patient, imaging findings, and operative findings.
Figure 3 Computed Tomography angiogram (A) and volume rendering imaging (B) showing pseudocoarctation of aorta.
116
S. Singh et al.
Pseudocoarctation Illustrative Case 2 A 49 year-old gentleman presented with a week-long history of left sided sharp chest pain radiating to the back and worse with inspiration. At age 26, he was diagnosed with testicular cancer that was successfully treated with orchiectomy and radiation. Physical examination revealed a normal JVP, peripheral pulses, and blood pressures in both upper and lower extremities. Auscultation of the heart revealed a 2/6 early diastolic murmur best heard at the left lower sternal border. Transthoracic echocardiogram (TTE) showed a trileaflet aortic valve with an abnormal anterior cusp resembling
healed endocarditis. Transoesophageal echocardiography (TEE) showed moderate aortic insufficiency with leaflet margins thickening which impaired cooptation. Computerised tomographic angiogram of the chest showed pseudocoarctation of the aorta (Figure 3). The patient was prescribed a short course of non-steroidal anti-inflammatory medication for musculoskletal symptoms with good resolution. Annual follow up with echocardiogram and endocarditis prophylaxis was recommended.
Discussion Pseudocoarctation of the aorta is a congenital anomaly occurring when embryonic compression of the third through
Table 2 Comparing coarctation, pseudocoarctation and hypoplastic arch. Coarctation CLINICAL FEATURES
Pseudocoarctation
Hypoplastic Arch
Male > female
Male > female, average age diagnosed
Hypertension in the upper
43 years.
Shortness of breath, fatigue,
extremities, brachialfemoral delay, and low or
Hypertension. Unequal BP in extremities may or may not be
weakness, syncope, exertional headache,
unobtainable arterial blood
present. Dyspnoea, dysphagia and
hypertension.
pressure in the lower
chest pain or back pain suggests
Systolic murmur in 2nd left
extremities.
complications. Patient may also be
intercostal space. Absent or
Continuous cardiac
completely asymptomatic.
unequal pulse, asymmetric
murmurs present due to
Various cardiac murmurs heard along
blood pressure in
collateral flow. Mid systolic
the sternal borders, base of neck or
extremities.
murmur in interscapular area due to flow across the
interscapular region, along with those of associated cardiac abnormalities.
narrowing.
Associated with vein of Galen
Associated with Turner’s
malformation, Turner’s.
syndrome CHEST X-RAY
Notching in posterior third
Widening of superior mediastinum
Normal sized heart with
of 3rd to 8th ribs, usually
and double aortic arch.
prominent aortic knob.
apparent between ages of
High aortic arch. Superior mediastinal
4-12. Sign of 3 on
mass.
oesophagogram due to preand post-coarct dilation. ECHOCARDIOGRAM
CT/MRA
CARDIAC CATHETERISATION
Narrowing within the
Dilation and kinking in proximal
Hypoplastic arch with
lumen of the proximal
descending aorta. Discontinuity of the
coarctation.
descending thoracic aorta.
arch.
Abnormal flow in collateral
Aneurysm below the level of
vessels seen on colour flow and Doppler.
pseudocoarctation.
Location and severity of the
Kinked and elongated arch, tapered
Hypoplastic arch.
coarctation, collaterals and
descending aorta and corkscrew
Associated cardiovascular
associated cardiac
appearing segment of aorta. May also
defects.
abnormalities.
show aneurysmal dilations.
Gradient across the narrow
No or
