1. Congenital Heart Disease: Outcome in Patients with Single Ventricle
Jane E. Crosson, MD
Director, Pediatric Electrophysiology and Adult Congenital Heart Disease Program

2. Single Ventricle: The most severe form of congenital heart disease
Characterized by only one usable ventricle
Final common pathway: Fontan procedure
Surgical palliation that relies on “downhill” flow from veins to pulmonary arteries, with no pump to the lungs
Long-term complications are numerous

3. Most common forms of SV Tricuspid atresia
Variable presentation at birth
Eventual palliation Fontan procedure
Best long-term survival of all single ventricles, due to systemic left ventricle
Hypoplastic left heart syndrome
Includes aortic and mitral atresia, most severe form of HLHS
Need multiple surgeries
Survival rate has improved over time
Relies on systemic right ventricle
RV failure, tricuspid regurgitation common

4. Tricuspid Atresia: Anatomic Variation
Also called Hypoplastic Right Heart Syndrome
Atretic tricuspid valve
Small right ventricle fed via a VSD
Obligate right to left flow across atrial septum
Normal or malposed great arteries
+/- PS, AS, coarctation

5. Hypoplastic Left Heart Syndrome
Aortic atresia/severe stenosis
Mitral atresia/stenosis
Hypoplastic LV
Arch obstruction
Ductal and PFO dependent

6. More common forms of SV
Pulmonary atresia with intact ventricular septum
Some can undergo 2 ventricular repair, if RV large enough, and no coronary arteries are dependent on the high pressure RV
Those with very small RV, and RV dependent coronary circulation, require Fontan palliation
Major risk: ischemia with sudden death

7. Other forms of SV Double-inlet single left ventricle
Unbalanced AV canal
Primitive heart with single atrium and ventricle (“frog heart”)

8. Modified Fontan: Extracardiac Conduit
Replaced lateral tunnel by late ‘90s in most centers
Advantages:
Can be done without circ arrest (or even CPB)
Best fluid dynamics
No intra-atrial suture line
Disadvantages:
Fixed conduit size
Epicardial pacing only

9. What Can Go Wrong: Plumbing
AV valve regurgitation
Aortic regurgitation
Sub-aortic obstruction
Arch obstruction
PA hypoplasia, obstruction, compression by aorta
Pulmonary venous obstruction
Baffle leaks
Surgical re-intervention in ~25% of Fontan patients

10. What Can Go Wrong: Physiology
Arrhythmias
Heart block
Sinus node dysfunction
Atrial arrhythmias
Ventricular arrhythmia
Ventricular dysfunction
Right ventricle especially vulnerable
Causes: chronic cyanosis, chronic volume overload, dyssynchrony
Thrombus, PE
AP collaterals
Pulmonary AVMs
Chronic effusions
Protein-losing enteropathy
‘Cirrhosis’

11. Single ventricle long-term follow-up

12. Actuarial survival in hypoplastic left heart syndrome.
 Actuarial survival after staged surgical management of the hypoplastic left heart syndrome. Data are mean (SD).
McGuirk S P et al. Heart 2006;92:
©2006 by BMJ Publishing Group Ltd and British Cardiovascular Society

13. Improved early survival in HLHS
 Serial estimates of early mortality with 95% confidence interval. (A) Running estimate. (B) Exponentially weighted moving average with 5% down weighting for each case.
McGuirk S P et al. Heart 2006;92:
©2006 by BMJ Publishing Group Ltd and British Cardiovascular Society

14. Neurodevelopmental Outcome in HLHS
Mahle, W. T. et al. Pediatrics 2000;105:
Copyright ©2000 American Academy of Pediatrics

15. Parental assessment of functional status of children with HLHS
Health
Excellent 52 (45.2%)   
Good 40 (34.8%)   
Fair 14 (12.2%)   
Poor 10 (8.7%)
Limitations to activity   
None 59 (51.3%)   
Slight 43 (37.4%)   
Significant 12 (10.4%)   
Severe 2 (1.7%)

16. Number of cardiac medications required in children with HLHS
Mahle, W. T. et al. Pediatrics 2000;105:
Copyright ©2000 American Academy of Pediatrics

17. Harrison

18. Ventricular ejection fraction in Fontan patients

19. Short and long term needs of Fontan patients
Top-notch medical care
Early school readiness intervention
Life-long access to Adult Congenital Heart Disease experts
Funds for pacemakers, repeat surgeries
Job training
Option for heart transplant
Adult patients with single ventricle are the most poorly insured and most in need of services

20. Cardiac Rhythm Issues in Pediatrics
Almost all arrhythmias can be well-controlled with medication, catheter ablation of the arrhythmia focus, pacemaker and/or defibrillator (ICD)
No limitations to work or school for most patients
Those with pacemakers and ICDs have some limitations regarding work environment
No extremely physical work
No close exposure to high-voltage

21. Sudden Cardiac Death in Children
Rare in children as compared to adults
1.3 to 8.5 per 100,000 patient-years
Often 2ndary to hypertrophic cardiomyopathy, myocarditis or congenital heart disease
SIDS/airway most common cause in infants
Most common primary arrhythmias with risk of SCD are:
Long QT syndrome
Catecholaminergic polymorphic ventricular tachycardia
Arrhythmogenic right ventricular cardiomyopathy
Brugada syndrome

22. Sudden Cardiac Death in Children
Overall survival rate for out-of hospital cardiac arrest is low, ~10%, including SIDS
As with adults, witnessed arrest has better outcome; unwitnessed arrest survival rate ~0%
If successfully resuscitated, cognitive sequelae can be significant, including lifelong need for complete support.

23. Cardiac Rhythm Issues in Pediatrics: Patient Needs
Access to medication, catheter techniques and devices as needed
Time off from work/school to see physicians/ have procedures
Rare need for disability unless associated with co-morbidities such as congenital heart disease (not uncommon association), or sequelae from SCD resuscitation