Unbalanced AVC: When is it
Time to Bail?
David M. Overman
Division of Pediatric Cardiac Surgery
The Children’s Heart Clinic
Chief, Division of Cardiovascular Surgery
Children’s Hospitals and Clinics of Minnesota
A Disclaimer
When is it time to bail?
A Disclaimer
When is it time to bail?
I DON’T REALLY KNOW.
A Disclaimer
When is it time to bail?
I DON’T REALLY KNOW.
(and neither do you)
Unbalanced AVSD
Precise diagnosis
– When does AVSD become unbalanced?
The Challenges of UAVSD
Proper selection of surgical strategy
– When must biventricular repair be abandoned?
uAVSD: BVR or UVR?
uAVSD: BVR or UVR?
uAVSD: BVR or UVR?
“Discordant pursuit of BVR�is more frequent
than discordant pursuit of UVR, likely driven
by an intuitive notion that ‘two ventricles are by an intuitive notion that ‘two ventricles are
better than one’. Discordant BVR is more costly
in terms of survival than discordant UVR.”
Hickey EJ, et al. JTCVS 134(6), Dec 2007.
BVR or UVR : Is uAVSD the same as
“borderline left heart”??“borderline left heart”??
Background
Uncommon
Paucity of outcomes data
Nuanced surgical strategies
Unbalanced AVSD
Nuanced surgical strategies
Variable and complex anatomy
Multiple important comorbidities
Background
Uncommon
Paucity of outcomes data
Nuanced surgical strategies
Unbalanced AVSD
Nuanced surgical strategies
Variable and complex anatomy
Multiple important comorbidities
uAVSD Literature
n = 19
BVR only
Long axis ratio (LAR): LV/RV
3 early failures (death, OHT)
3 late reoperations (event free survival 56% @ 10 years)
uAVSD Literature
n = 38n = 38
32 BVR, 6 SVR
AVVI (RAV/LAV) and ratio RV length/LV length
Four early deaths (3 BVR)
Six early reoperations (All BVR)
No late follow-up data
Background
Uncommon
Paucity of outcomes data
Nuanced surgical strategies
Unbalanced AVSD
Nuanced surgical strategies
Variable and complex anatomy
Multiple important comorbidities
Background
Uncommon
Paucity of outcomes data
Nuanced surgical strategies
Unbalanced AVSD
Nuanced surgical strategies
Variable and complex anatomy
Multiple important comorbidities
Anatomic Considerations
Aortic arch obstruction
Systemic and pulmonary venous anomalies
VSD morphology
Complex valve morphology
Atrial septal malalignment
Anatomic Considerations
Aortic arch obstruction
Systemic and pulmonary venous anomalies
VSD morphology
Complex valve morphology
Atrial septal malalignment
Anatomic Considerations
Aortic arch obstruction
Systemic and pulmonary venous anomalies
VSD morphology
Complex valve morphology
Atrial septal malalignment
Anatomic Considerations
Aortic arch obstruction
Systemic and pulmonary venous anomalies
VSD morphology
Complex valve morphology
Atrial septal malalignment
Leaflet Dysplasia & Deficiency
Courtesy of Rachid Idriss
Farouk Idriss Archive
Children’s Memorial Hospital
Anatomic Considerations
Aortic arch obstruction
Systemic and pulmonary venous anomalies
VSD morphology
Complex valve morphology
Atrial septal malalignment
Atrial Septal Malalignment
Courtesy of Rachid Idriss
Farouk Idriss Archive
Children’s Memorial Hospital
Background
Uncommon
Paucity of outcomes data
Nuanced surgical strategies
Unbalanced AVSD
Nuanced surgical strategies
Variable and complex anatomy
Multiple important comorbidities
Balanced AVSD
Balanced AVSD Outcomes: Biventricular Repair
balanced complete AVSD
(STS National Congenital Database)
Discharge mortality 2.3%
Permanent pacer 1.5%
Reop for bleeding 1.3%
Neuro deficit 0.7%
Hospital LOS 14.6 days
-STS National Congenital Database Fall 2011 Harvest
Severely Unbalanced
AVSD
Severely Unbalanced
AVSD Outcomes: Norwood Palliation
not specific to uAVSD
(STS National Congenital Database)
MORTALITY
Norwood 17.1%Norwood 17.1%
BCPS 1.4%
Modified Fontan 1.3%
-STS National Congenital Database
Fall 2011 Harvest
Severely Unbalanced
AVSD Outcomes: Norwood Palliation
not specific to uAVSD
(STS National Congenital Database)
MORTALITY
Norwood 17.1%Norwood 17.1%
BCPS 1.4%
Modified Fontan 1.3%
-STS National Congenital Database
Fall 2011 Harvest
UVR and Trisomy 21
PCCC: All Fontans (n=2853)
Fontan with Trisomy 21 (n=17)
Overall Fontan Mortality: 10%
Fontan/Trisomy 21 Mortality: 35% (p=0.001)
UVR and Trisomy 21
BVR
Trisomy 21: BVR or UVR?
Norwood @ 8d
Glenn @ 4m
Hospital stay 6m
Fontan @ 44m
CMV viral sepsis
RVEF 13%RVEF 13%
Hospice
Died @ 5 yrs
Trisomy 21: BVR or UVR?
Norwood @ 10d
Revision MBTS @ 10w
Sildenafil
BiV Conversion @ 6m
Systemic RVP, MS =15 torrSystemic RVP, MS =15 torr
Reop MS/LVOTO @ 13 m
RVP = 80+, MS = 14 torr
Diminished RV fct @ 17m
Current resp illness on vent
LVEDD
10 (z = -5.6) 21 (z = -0.65)
uAVSD: BVR or UVR?
Ventricular hypoplasia
Malalignment of Atrioventricular JunctionMalalignment of Atrioventricular Junction
Predicting BVR:
Ventricular Hypoplasia
Ventricular “competence”– Ability to sustain full cardiac output
Predicting BVR:
Ventricular Hypoplasia
Ventricular “competence”
Imprecise measurementImprecise measurement– “Apex forming”
– 2D echo geometry (LV length/width)
– Volume formulae
• Echo: unreliable
• MRI: impractical
Predicting BVR:
Ventricular Hypoplasia
Right Dominant Left Dominant
uAVSD: BVR or UVR?
Ventricular hypoplasia
Malalignment of Atrioventricular JunctionMalalignment of Atrioventricular Junction
AV Malalignment
Apportionment of AV valve over the underlying
ventricles
Anatomy of “inflow physiology”
AVVI
Atrioventricular Valve Index (AVVI)
– Subcostal LAO view
– Measure area of common AV valve apportioned over each ventricle
– LAVV:RAVV or RAVV:LAVV
AVVI Measurement
RAVV
LAVV
CHSS Lookback
Modified AVVI
– LAVV:Total AVV
Left DominantRight Dominant
0.5
Overman DM, et al. WJSPCHS 1(1), Sept 2008
mAVVI: Strategy & Outcome
N=305
Median =0.47
*Jegatheeswaran et al. Circ 2010;122;S209-S215
Predicting BVR: Beyond AVVI
Left Ventricular Inflow Index (LVII)
RV/LV Inflow AngleRV/LV Inflow Angle
Predicting BVR: LVII
Narrowest width into ventricle at level of AV valve
– Indexed to width of common AV valve annulus
22 pts w/ right dominant uAVSD undergoing BVR
– 4/22 died
No survivors with LVII <0.5No survivors with LVII <0.5
Predictive of survival after BVR in right dominant uAVSD
*Swast et al. Usefulness of Left Ventricular Inflow Index to Predict
Successful Biventricular Repair in Right Dominant Atrioventricular Canal.
Am J Cardiol 2011 Jan; 107(1): 103-9.
RV/LV Inflow Angle - Balanced
154°
RV/LV Inflow - Unbalanced
82°
Predicting BVR: RV/LV Inflow Angle
116 pts with right dominant uAVSD or bAVSD
Cluster analysis: 3 homogenous subgroups in strategy
and outcome
RV/LV inflow angle most sensitive discriminator of
subgroups
*Cohen et al. Echocardiographic Features Defining Right Ventricle
Dominant Unbalanced Atrioventricular Septal Defect: A Multi-Institutional
Congenital Heart Surgeons Society Study. Poster presentation. AHA Scientific Sessions,
November 2011. Manuscript in preparation
Beyond Prediction:
Growth Induction Strategies
1995 – 2005, n = 24
Staged Palliation (10), Valve “repartitioning” (9), Repair with residual (5)
All achieved BVR
Mid term survival 88%
Z Scores (n=7)
AV valves: (-1.1 to -6.5) (-2.1 to +1.8)
Ventricles: (-3.6 to -7.5) (-1.0 to +2.0)
Conclusions
Ability to predict ventricular “competence” after
BVR is limited
Malalignment of the AV junction is an important Malalignment of the AV junction is an important
factor in the viability and sustainability of BVR
Conclusions
LVII and RV/LV Inflow Angle may augment the
utility of AVVI in predicting successful BVR
Surgical strategies aimed at inducing growth Surgical strategies aimed at inducing growth
warrant further investigation but current data
supporting this approach are less than robust
Conclusions
Clarification of the interplay of these many factors
is needed to optimize outcomes in uAVSD
A prospective, multi-institutional study will be A prospective, multi-institutional study will be
required to adequately power such an
investigation
Conclusions
Unbalanced Atrioventricular Septal Defect:
A CHSS Inception Cohort Study
First patient enrolled December 2011
Unbalanced AVC: When is it
Time to Bail?
David M. Overman
Division of Pediatric Cardiac Surgery
The Children’s Heart Clinic
Chief, Division of Cardiovascular Surgery
Children’s Hospitals and Clinics of Minnesota