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CLINICAL-SURGICAL CORRELATION
Tetralogy of Fallot with an Anomalous Course of the Brachiocephalic Vein
Larissa Alves Leite Matos
Fundação Faculdade Regional de Medicina de São José do Rio Preto/Faculdade de Medicina de São José do Rio Preto, Brazil
Isaac Azevedo Silva
Fundação Faculdade Regional de Medicina de São José do Rio Preto/Faculdade de Medicina de São José do Rio Preto, Brazil
Fernando Cesar Gimenes Barbosa Santos
Fundação Faculdade Regional de Medicina de São José do Rio Preto/Faculdade de Medicina de São José do Rio Preto, Brazil
Ulisses Alexandre Croti ulissesacroti@gmail.com
Fundação Faculdade Regional de Medicina de São José do Rio Preto/Faculdade de Medicina de São José do Rio Preto, Brazil
Brazilian Journal of Cardiovascular Surgery, vol. 38, no. 5, e20230047, 2023
Sociedade Brasileira de Cirurgia Cardiovascular
Received: 06 February 2023
Accepted: 10 February 2023
CASE PRESENTATION
Clinical Data
Male, 11-month-old, weight: 7.7 Kg, height: 0.72 m, referred to our service
diagnosed with Tetralogy of Fallot (TOF), presenting classic episodes of
cyanotic spells. From a rural area in the Northern region of Brazil; due to lack
of congenital heart service in this location, he waited several months for
surgical intervention.
Physical examination showed an ejection systolic murmur at left sternal border.
Regular pulse at 112 bpm and pulse oximetry with 92% oxygen saturation.
Remaining physical findings were unremarkable.
TECHNICAL DESCRIPTION
Chest Radiography
Visceral and thoracic situs solitus. Cardiothoracic ratio of
0,53. Slightly reduced pulmonary vascular markings.
Electrocardiography
Sinus rhythm with normal axis for age (S QRS + 100°), PR interval of 120 ms, QRS
of 80 ms, and QTc of 424 ms. After surgical repair, patient developed right
bundle branch block.
Echocardiography
Situs solitus in levocardia, usual venoatrial, atrioventricular,
and ventriculoarterial connections. Malalignment of conal septum with a large
perimembranous ventricular septal defect, extending to the outlet portion of the
right ventricle, typical of TOF. Atrial septal defect of 12 mm.
Hyperthrophic right ventricle with significant subpulmonary and valvar pulmonary
stenosis, outlet right ventricle, and pulmonary valve peak and medium gradient
were 95 mmHg and 60 mmHg, respectively.
Pulmonary valve with thickened semilunar valves and commissural fusion measuring
7.0 mm (Z score: -0.59), with normal-sized pulmonary trunk and pulmonary
arteries branches. Aortic valve dilatation of 14.2 mm (Z score: +4.95). Normal
biventricular function.
Computed Tomography Angiography
Situs solitus in levocardia. Systemic venous return through the
vena cava to the right atrium with slightly increased dimensions. Confirmation
of observed finding during surgical repair of left brachiocephalic vein (LBCV)
with anomalous retrotracheoesophageal course, configuring a U-shaped garland
vein (Figures 1 A to D). Narrowing of left
main bronchus at crossing level with the anomalous brachiocephalic vein.
Fig. 1
Contrast-enhanced computed tomography showing axial (A) and
sagittal (B) images of the U-shaped retroesophageal course of left
brachiocephalic vein (white arrow) which joins the right
brachiocephalic vein to form the superior vena cava. Volume rendered
image as seen from posterior aspect (C) and view from the top (D)
shows abnormal course of left brachiocephalic vein into U- shaped
vein. (red: trachea).
Postoperative findings of complete TOF repair with interventricular communication
closure with patch, signs of enlargement of right ventricular outflow tract with
pulmonary valve/subvalvular region narrowing, dilatation of the left pulmonary
artery, and aorta at the sinus of Valsalva level.
Supra-aortic branches anatomical variant (1st branch: common origin of
right and left common carotid arteries; 2nd branch: left vertebral
artery origin directly from aortic arch; 3rd branch: left subclavian
artery).
Operation
Patient was scheduled for complete TOF repair. In the operating room, after
standard median sternotomy, no LBCV was found, but a vertical left vein
resembling left vena cava (LVC). However, there was no connection between this
LVC and the heart. Therefore, surgical dissection was extended through
retroaortic region to retrotracheoesophageal space. Finally, this LBCV came to
join the superior vena cava, configuring the U-shaped garland vein.
Next, procedure was performed as planned, with bicaval and aortic cannulation.
Right ventricular outflow tract was relieved by myotomy. Pulmonary valve was
corrected by commissurotomy. Ventricular septal defect closed with bovine
pericardial patch. Right ventricular outflow tract and pulmonary trunk were
enlarged with bovine pericardial patch. And atrial septal defect was closed with
a bovine pericardial patch.
A transesophageal echocardiogram after cardiopulmonary bypass removal showed good
results.
COMMENT
The spectrum of systemic venous anomalies varies widely and is usually asymptomatic.
This case is an anomalous course of an LBCV, with intraoperative diagnosis.
The normal course of the left brachiocephalic (innominate) vein is from left to
right, anterior to the aortic arch in the superior mediastinum, joining the right
brachiocephalic (innominate) vein forming the right superior vena cava.
The anomalous LBCV (ALBCV) was first described by Kerschener in 1888[1]. Webb et al.[2] described computed tomographic findings in 1982. In
a study published in 2010, the incidence of ALBCV was 0.02% in > 4,800 patients
without congenital heart disease, but 28 times more prevalent in patients with
congenital heart defects[3].
The association between systemic venous return variations and TOF was found in about
15% of 973 angiographies reviewed by Pandey et al.[4] Persistence of left superior vena cava (11.5%) was
the majority, and anomalous course of the brachiocephalic vein was seen in 4% of
cases.
Kahkouee et al.[5] focused on ALBCV
evaluation of > 1,300 patients and found 22 cases. When present, this anatomic
variation was associated with TOF in more than half of the cases. It is worth
mentioning, however, that these authors have accounted the retroaortic course of the
LBCV.
In this specific case, ALBCV has retrotracheoesophageal course, with appearance of
the architectural garland configuration[6]. The incidence of this particular case is not known since most
studies have considered all variations of LBCV as aberrant.
The anomalous brachiocephalic vein is rare, however, knowing the existence of these
anomalies associated to TOF is relevant when undergoing invasive procedures and
surgical approach. Differing from LVC persistence, in this setting, no modifications
in venous canulation for cardiopulmonary bypass were necessary and they did not
affect the surgical technique or final postoperative result.
