656

CASE REPORT
AVLONITIS ET AL
SHUNT OCCLUSION AFTER CLOPIDOGREL CESSATION

The authors thank Shirley McCartney, PhD, for editorial assistance and Andy Rekito, MS, for illustrative assistance.

References
1. Aleksic I, Sommer SP, Kottenberg-Assenmacher E, et al.
Cardiac operations in the presence of meningioma. Ann
Thorac Surg 2009;88:1264 – 8.
2. Grigore AM, Grocott HP, Newman MF. Anesthetic management of a patient with a brain tumor for cardiac surgery.
J Cardiothorac Vasc Anesth 2000;14:702– 4.
3. Kurisu K, Hisahara M, Ando Y, Tominaga R. An unusual
manifestation of brain tumor: development of delayed hemiplegia after cardiopulmonary bypass. J Card Surg 2007;22:
417– 8.
4. Maeda K, Gotoh H, Chikui E, Furusawa T. Intratumoral hemorrhage from a posterior fossa tumor after cardiac valve surgery– case report. Neurol Med Chir (Tokyo) 2001;41:548 –50.
5. Slavin ML. Acute remitting visual loss after coronary artery
bypass surgery caused by a suprasellar meningioma. Am J
Ophthalmol 1987;104:434 –5.
6. Tashiro T, Zaitu R, Nakamura K, et al. Off-pump CABG for a
patient with a brain tumor. Ann Thorac Cardiovasc Surg
2000;6:193–5.
7. Harris DN, Oatridge A, Dob D, Smith PL, Taylor KM, Bydder
GM. Cerebral swelling after normothermic cardiopulmonary
bypass. Anesthesiology 1998;88:340 –5.
8. Ellis JA, D’Amico R, Sisti MB, et al. Pre-operative intracranial
meningioma embolization. Expert Rev Neurother 2011;11:
545–56.

FEATURE ARTICLES

Occlusion of Modified BlalockTaussig Shunt After Clopidogrel
Cessation
Vassilios Spiridon Avlonitis, MD, PhD,
Silvia Planas, MD, Alison M. Hayes, MBBS, FRCP, and
Andrew Parry, FRCS (CTh)
Bristol Heart Institute, and Histopathology Department, Bristol
Royal Infirmary, Bristol; and Bristol Royal Hospital for Sick
Children, Bristol, United Kingdom

It has been suggested previously that rebound hypercoagulability may be responsible for morbidity and mortality following clopidogrel cessation in adults with
acute coronary syndrome. We report a case of acute
occlusion of a modified Blalock-Taussig shunt in an
infant after clopidogrel discontinuation.
(Ann Thorac Surg 2012;93:656 – 8)
© 2012 by The Society of Thoracic Surgeons

A

cute occlusion of a modified Blalock-Taussig shunt
(MBTS) is a potentially catastrophic complication.
A recent study showed that patients treated with clopidogrel after acute coronary syndrome are at high risk of
acute myocardial infarction and death early after discontinuation of the drug [1]. This finding suggested a possi-

Accepted for publication July 26, 2011.
Address correspondence to Dr Avlonitis, Bristol Heart Institute, Bristol
Royal Infirmary, Upper Maudlin St, Bristol, BS2 8HW, United Kingdom;
e-mail: avlonitis@hotmail.com.

© 2012 by The Society of Thoracic Surgeons
Published by Elsevier Inc

Ann Thorac Surg
2012;93:656 – 8

ble rebound effect associated with abrupt clopidogrel
cessation. We report a case of acute thrombosis of a
MBTS following clopidogrel discontinuation.
A male child was born at 40 weeks’ gestation with an
antenatal diagnosis of tricuspid and pulmonary atresia
and ventricular septal defect. At birth, echocardiography
showed several major aortopulmonary collateral arteries
(MAPCAs), atrial septal defect, tricuspid atresia, two
ventricular septal defects, small right ventricle, pulmonary atresia, and right aortic arch. At 5 days of age, he
underwent cardiac catheterization, and at 7 weeks of age
he underwent unifocalization of all MAPCAs with augmentation of the central portion using autologous pericardium. A MBTS was performed between the left subclavian artery and the unifocalized arteries using a
3.5-mm polytetrafluoroethylene graft. The operation and
postoperative recovery were uneventful, and the patient
was discharged 9 days later, receiving aspirin (5 mg/kg)
and clopidogrel (0.2 mg/kg). Oxygen saturations at discharge were 75%.
At follow-up, at age 20 weeks, the child exhibited
dyspnea with oxygen saturations between 70% and 75%.
Echocardiography showed reduced flow in the left pulmonary artery, and cardiac catheterization confirmed
stenosis of the left MAPCA as it passed over the left
bronchus. The decision was made to perform an additional left MBTS to the left neopulmonary artery. The
clopidogrel was discontinued in preparation for surgery,
but the operation had to be postponed because the child
developed viral conjunctivitis. Aspirin treatment was
restarted, but clopidogrel was not because of the imminent surgery.
The child was taken to surgery 7 days later with an
oxygen saturation of 75%. After performing a left thoracotomy, he became increasingly cyanotic and the oxygen
saturation fell dramatically, leading to bradycardia. The
diagnosis of occlusion of the previous MBTS was made.
The child was immediately positioned supine, cardiopulmonary resuscitation was performed, and cardiopulmonary bypass was established through cannulation of the
left femoral vessels. A repeated sternotomy was performed. The previous shunt was excised and found to be
occluded with a white granular clot. A new 3.5-mm
central shunt was constructed between the left side of the
ascending aorta and the branch pulmonary arteries.
Cardiopulmonary bypass was discontinued on low-dose
inotropic support, protamine was administered, the femoral vessels were repaired, and the chest was closed.
The patient was transferred to the intensive care unit.
During the first 24 hours, he had episodes of desaturation. Because of the preceding arrest, there were concerns regarding neurologic status. Electroencephalography showed nonconvulsive status epilepticus, which was
treated with phenytoin. On the fifth postoperative day,
the patient developed anisocoria. Magnetic resonance
imaging of the brain showed diffuse edema and changes
consistent with severe diffuse ischemic damage. The
child deteriorated and died on the 12th postoperative
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doi:10.1016/j.athoracsur.2011.07.071

Ann Thorac Surg
2012;93:656 – 8

CASE REPORT
AVLONITIS ET AL
SHUNT OCCLUSION AFTER CLOPIDOGREL CESSATION

657

day. Histologic examination of the occluded shunt
showed no evidence of fibrin thrombi (Fig 1).

Comment
The MBTS is commonly used in neonates with cyanotic
heart disease to achieve palliation and stability until
definitive surgical correction can be performed. While
many centers are moving away from this method as
palliation for two-ventricle circulations, there is no alternative in patients with pulmonary atresia who require
single-ventricle palliation.
One of the most lethal complications of MBTS is acute
occlusion of the shunt. Li and colleagues [2] reported
1-year Kaplan-Meier event rates for shunt occlusion of
11% and 16% for closed and open (with cardiopulmonary
bypass) shunts, respectively. The United Kingdom data
show a 30-day and 1-year mortality for arterial shunt of
12.6% and 34%, respectively [3]. Studies have shown that
shunts of smaller caliber are more prone to stenosis or
occlusion [4, 5].
Although the evidence for the benefits of anticoagulation in preventing MBTS stenosis and occlusion
have been conflicting, it is common practice to administer heparin intraoperatively and commence longterm aspirin postoperatively [6]. In a large retrospective study, Li and colleagues [2] showed a lower risk of
shunt occlusion and death in infants receiving aspirin.
The advantages of other modern antiplatelet agents
have not been investigated. Our patient was enrolled
in a prospective, randomized controlled trial investigating the effects of best treatment with or without
clopidogrel in prevention of MBTS thrombotic occlusion (CLARINET Study). The clopidogrel was discontinued before urgent reoperation, when flow to the left
lung was shown to be severely compromised. During
surgery, shunt occlusion occurred with catastrophic
results. Gross examination of the occluded graft
showed a white granular clot. Subsequent histologic
examination confirmed absence of fibrin thrombus,
suggesting that the clot was predominantly platelet in
origin.
The addition of clopidogrel to aspirin has been
shown to reduce cardiovascular risk in adult patients
with acute coronary syndrome undergoing percutane-

ous coronary intervention (PCI). However, Ho and
colleagues [1] reported recently that sudden clopidogrel cessation in a cohort of patients with acute
coronary syndrome treated medically or with PCI was
followed by a clustering of adverse cardiovascular
events. This study has raised the possibility that the
early benefit of clopidogrel treatment in these patients
may be counterbalanced by a rebound hypercoagulable effect after discontinuation of the drug [7]. This
clinical observation may be supported by pharmacologic evidence. An increase in the expression of activation markers in adenosine diphosphate-stimulated
platelets has been observed in healthy volunteers after
clopidogrel discontinuation [8].
No conclusions regarding cause and effect can be
drawn from our case report. However, in light of the
observations in the adult literature, patients who require clopidogrel cessation should be carefully managed and followed. This therapy needs to be evaluated
with randomized trials extending far beyond clopidogrel cessation in order to determine whether early
benefits are counterbalanced by later adverse events
associated with hypercoagulability following discontinuation of the drug. This evaluation has already been
started by a modification in the CLARINET study, with
long-term outcomes being measured.
A.P. was Chief Investigator for United Kingdom for the CLARINET
study (http://clinicaltrials.gov/ct2/show/NCT00833703), examining the benefits of clopidogrel in addition to aspirin in children
after Modified Blalock-Taussig shunt.

References
1. Ho PM, Peterson ED, Wang L, et al. Incidence of death and
acute myocardial infarction associated with stopping clopidogrel after acute coronary syndrome. JAMA 2008;299:
532–9.
2. Li JS, Yow E, Berezny KY, et al. Clinical outcomes of palliative
surgery including a systemic-to-pulmonary artery shunt in
infants with cyanotic congenital heart disease: does aspirin
make a difference? Circulation 2007;116:293–7.
3. The Information Centre: Central Cardiac Audit Database.
Available at http://www.ccad.org.uk/congenital. Accessed
June 13, 2011.
4. McKay R, de Leval MR, Rees P, Taylor JF, Macartney FJ, Stark
J. Postoperative angiographic assessment of modified Bla-

FEATURE ARTICLES

Fig 1. Histologic section of the occluded
shunt. (A) Hematoxylin-eosin stain shows
eosinophilic material within the lumen, focally attached to the underlying wall (arrows)
in keeping with a thrombus. (B) Martius
Scarlet Blue trichrome stain, which selectively
stains fibrin in red. The stain demonstrates
the absence of fibrin within the thrombus (arrows), which is composed of platelets only.

658

CASE REPORT
MURALIDARAN ET AL
MODIFIED STARNES PROCEDURE FOR SEVERE TRICUSPID REGURGITATION

lock-Taussig shunts using expanded polytetrafluoroethylene
(Gore-Tex). Ann Thorac Surg 1980;30:137– 45.
5. Tamisier D, Vouhe PR, Vernant F, Leca F, Massot C, Neveux
JY. Modified Blalock-Taussig shunts: results in infants less
than 3 months of age. Ann Thorac Surg 1990;49:797– 801.
6. Ahmad U, Fatimi SH, Naqvi I, et al. Modified Blalock-Taussig
shunt: immediate and short-term follow-up results in neonates. Heart Lung Circ 2008;17:54 – 8.
7. Cundiff DK. Benefit of clopidogrel for acute coronary syndrome and percutaneous coronary interventions in doubt due
to rebound adverse events. Am J Cardiol 2008;102:248.
8. Weber AA, Braun M, Hohlfeld T, Schwippert B, Tschope D,
Schror K. Recovery of platelet function after discontinuation
of clopidogrel treatment in healthy volunteers. Br J Clin
Pharmacol 2001;52:333– 6.

Modified Starnes Procedure in a
Neonate With Severe Tricuspid
Regurgitation
Ashok Muralidaran, MD, Richard W. Kim, MD,
Gary S. Kopf, MD, Nicholas P. Pietris, MD,
Bevin P. Weeks, MD, Vaughn A. Starnes, MD, and
Toshiharu Shinoka, MD, PhD
Section of Pediatric Cardiovascular Surgery, Yale University
School of Medicine, New Haven, Connecticut; Section of
Cardiothoracic Surgery, University of Southern California
Keck School of Medicine, Los Angeles, California; and Section
of Pediatric Cardiology, Yale University School of Medicine,
New Haven, Connecticut
FEATURE ARTICLES

We report a modification of the Starnes technique for
palliating severe tricuspid regurgitation associated with
a dysplastic right ventricle in a neonate, using a fenestrated pericardial patch allowing for unidirectional flow.
The patient eventually underwent a successful Glenn
shunt construction with a persistent reduction in right
ventricle size at 1 year follow-up.
(Ann Thorac Surg 2012;93:658 –9)
© 2012 by The Society of Thoracic Surgeons

I

nfants born with a dysplastic right ventricle, pulmonary atresia, and severe tricuspid regurgitation present a significant surgical challenge in the neonatal period. This includes patients with Ebstein anomaly as well
as a variety of other tricuspid valve and right ventricle
(RV) anomalies. Starnes and colleagues [1] described a
palliative approach in neonates with Ebstein anomaly in
whom the pulmonary blood flow is supplied by a systemic to pulmonary artery shunt and the tricuspid orifice
is closed with a pericardial patch [1]. This approach was
taken to prevent tricuspid regurgitation into the right
atrium. The original technique did not decompress the
RV, but a subsequent modification with a fenestrated
patch allowed for it [2]. We describe a further modification using a fenestration with a one-way flap valve that

Ann Thorac Surg
2012;93:658 –9

limits RV filling while allowing decompression, thus
encouraging shrinkage of the deformed RV.
A full-term female neonate (3.1 kg) with a prenatal
diagnosis of severe tricuspid regurgitation, pulmonary
atresia, and RV dysplasia was referred for surgical palliation with a ductal dependant pulmonary blood flow.
There were no coronary to RV fistulae.
An echocardiogram performed on the day of birth confirmed the severe tricuspid regurgitation with elevated RV
pressures. The study also revealed a patent ductus arteriosus with left-to-right shunt, an atrial septal defect and
pulmonary atresia with severely hypertrophied outflow
portion of a dilated RV. The branch pulmonary arteries
were small but confluent. The septal leaflet was noted to be
“tacked down” with a restrictive motion. The mitral and
aortic valves appeared normal. The chest radiograph revealed a cardiothoracic ratio of 0.95 with a massive right
atrium. The baby was hemodynamically stable on prostaglandin infusion with a systemic saturation of 88% on 21%
oxygen.
The patient was taken to the operating room on day
6 of life. Upon opening the right atrium on bypass with
standard bicaval cannulation, the tricuspid valve was
severely deformed with myxomatous leaflets and severe tricuspid regurgitation. The right atrium measured 10 cm.
Fresh autologous pericardium was harvested, sized to
the tricuspid orifice, and fenestrated with a 4-mm aortic
punch. By suturing a smaller pericardial patch along
three sides of the fenestration, we created a one-way flap
valve preventing antegrade flow into the right ventricular
chamber while allowing retrograde right ventricular decompression (Fig 1). The entire pericardial patch was
then sutured to the tricuspid annulus, with the medial
portion being sutured to the septal leaflet to avoid the
conduction system. In addition, we performed an atrial
septectomy, right atrial reduction, transection of the main
pulmonary artery followed by PA plasty with a homograft patch, and placement of a right-sided modified
Blalock-Taussig (BT) shunt with a 4-mm Polytetrafluoroethylene graft. The patient had an uneventful postoperative course and was discharged home on postoperative

Accepted for publication July 12, 2011.
Address correspondence to Dr Shinoka, Section of Pediatric Cardiovascular Surgery, Yale University School of Medicine, 333 Cedar St, Rm 204,
Boardman 2, PO Box 208039, New Haven, CT 06520; e-mail: toshiharu.
shinoka@yale.edu.

© 2012 by The Society of Thoracic Surgeons
Published by Elsevier Inc

Fig 1. The modified patch with a one-way flap valve covering the
4-mm fenestration.
0003-4975/$36.00
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