The Hemi-Mustard/Bidirectional Glenn Atrial Switch in the Anatomic ...

The Hemi­Mustard/Bidirectional
Glenn Atrial Switch in the
Anatomic Repair of cc­TGA:
Rationale and Midterm Results
S.P. Malhotra, V.M. Reddy, M. Qiu,
T. Pirolli, L. Barboza, O. Reinhartz, F.L. Hanley

No relationships to disclose

Anatomic repair of cc­TGA
• Support the systemic
circulation with the
morphological left ventricle
• Indication for intervention
– Decreased morphologic RV
function
– Progressive tricuspid
regurgitation
– VSD and/or PS, PA

OUR STRATEGY: Optimize outcomes of anatomic
correction of ccTGA with the bidirectional Glenn
–RV Unloading may
•Lessen impact of RV dysfunction
•Prolong life of RV­PA conduit
•Decrease tricuspid regurgitation
–Simplifying atrial baffle may
•Reduce sinus node dysfunction and atrial dysrhythmias
•Reduce systemic and pulmonary venous pathway
obstruction
•Be helpful with positional anomalies such as situs solitus
with dextrocardia, mesocardia and situs inversus

Patients
•48 patients between Jan 1993 to Sept 2009
•Rastelli­atrial switch (RAS): 25
–Pulmonary atresia: 22 (4 with PA/MAPCAs)
–Severe subpulmonary stenosis: 3
•Arterial­atrial switch (AAS): 23
–PAB required: 17
–PAB tightened: 8

Anatomic Details
• Morphology
–Positional anomalies in 35% (17/48)
–[S,L,L] 42
•Dextrocardia: 10
•Mesocardia: 1
–[I,D,D] 6
• VSD: 40
• Congenital HB: 4
• Tricuspid valve anomalies: 22
– Moderate or greater TR: 20
– Ebsteinoid valve: 10

Age distribution
20
18
16
14
12
10
8
6
4
2
0
< 1 yr 1­5 yr 5­10 yr 10­15 yr > 15 yr
•Median age 3.0 years
•Range 3.9 months to 24.0 years

Pre­DSO Procedures
Arterial­atrial group
Rastelli­atrial group
Pulmonary artery band 17 Modified Blalock­Taussig Shunt 17
PA Band tightening 8 Second Modified Blalock­Taussig Shunt 5
Bidirectional Glenn 2
VSD repair 1
Aortopulmonary window prior to
unifocalization
Unifocalization of MAPCAs to central
shunt
2
4
Pacemaker implantation 3 Bidirectional Glenn 5
Pacemaker implantation 1

Arterial­Atrial Switch (AAS)
Rastelli­Atrial Switch (RAS)
The “Hemi­Mustard” patch is always a simple circle, which
bends appropriately around the TV annulus and IVC orifice

Hemi­Mustard Atrial Switch
•Performed in 33/48 (70%) patients
•Conventional atrial baffle performed in 15
–Elevated PVR— 5 cases
–Anatomic considerations (LSVC to coronary sinus)­2 pts
–Surgeon preference— 8 pts (6 performed in the early
experience)

Outcomes
•Hospital mortality: 2.1% (1/48)
•No late deaths
•Postoperative ECMO support required in 2
patients
•Postoperative heart block: 21% (10/48)

Midterm results
100% complete follow­up
•Median follow­up 4.9 y, range 7 m ­ 16 y
•Biventricular function preserved in 87% of
survivors
–LV dysfunction:
moderate— 4 (2 AAS)
severe— 2
(2 AAS)
•NYHA functional class I in 43/47
•All acyanotic
•None have required cardiac transplantation

Hemi­Mustard results
• No baffle obstruction (0/33)
– Senning/Mustard experience: 5­15% 1,2
• No sinus node dysfunction (0/33)
– Senning/Mustard experience 35­46% 3,4
• 1 atrial tachyarrhythmia req ablation (1/33)
– Senning/Mustard experience 8­15% 3,4
• 2 BDG complications (Both age < 4 mo)
– takedown due to circular shunt
– neurologic complication­choreoathetosis
1
Helbing, et al. J Thorac Cardiovasc Surg. 1994;108:363­71.
2
Williams, et al. J Thorac Cardiovasc Surg. 1988;95:717­23.
3
Flinn, et al. N Engl J Med. 1984;310:1635­42.
4
Dos, et al. Heart. 2005;91:652­6.

Outcomes: TR
p=0.00004
•TR grade decreased from 2.2 ± 1.0 to 1.3 ± 0.5
•Post­DS TR was not affected if BDG used

Outcomes: Reoperation
• AAS­higher earlier need for reoperation
• RAS­late reoperation due to RV to PA
conduit replacement

Arterial­atrial switch outcomes
• Coronary complications: 2/23
– Reop LeCompte/LCA release performed
– Severe proximal RCA stenosis
• Neo­Aortic insufficiency: 2/23
– AVR required in one patient
– Both had PAB
30
25
• At higher risk for decreased
NYHA functional status
compared to Rastelli group
(p=0.013)
20
15
10
5
0
RAS
AAS
IV
III
II
I

Rastelli­atrial switch outcomes:
RVOT revision
• Hemi­Mustard group: 100% 10­yr freedom from RVOT
intervention
• Conventional atrial switch: 75% 5­yr and 50% 10­yr
• Hemi­Mustard lower risk of RVOT reintervention (p=0.019)

Conclusions
• The double switch with the BDG can be performed
with low morbidity and mortality
• Hemi­Mustard should be avoided in the youngest
patients that are at high risk for elevated PVR
• Advantages of the Hemi­Mustard:
–Decreases volume across RVOT and prolongs life
of RV to PA conduit
–Baffle complications minimized
–Sinus node dysfunction minimized
–Unloads the failing right ventricle
–Simplifies the atrial baffle technique