Single Ventricle Anomalies
1. Definition
Single dominant ventricle of R, L, or ? morphology
Variable atrio-ventricular connection
Rudimentary ventricle nearly always present
Pulmonary blood flow increased, decreased, or balanced
2. Morphologic Subsets
Tricuspid Atresia
Absent RA to RV communication
Ventricle of LV type
Double Inlet Left Ventricle (DILV)
Both atria connected to single dominant ventricle
Ventricle of LV type
Mitral Atresia
Absent LA to LV communication
Ventricle of RV type
Anomalies
Image
3. Palliative Procedures
Systemic - PA shunt - Pulmonary stenosis or atresia
Pulmonary artery band for CHF
Subaortic stenosis in 30 - 40%
Open or closed atrial septectomy
Bi-directional Glenn 4 - 8 months
4. "Definitive" Operations
Septation
Few truly suitable
Fontan procedure
Systemic venous to PA anastomosis
Fenestrated Fontan procedure
Calibrated opening from RA to LA
Applicable in marginal candidates
Lower perioperative morbidity
Extra-Cardiac Fontan Procedure
Tube from IVC to RPA
Cardiac transplantation
Septation Procedure
Total Cardiopulmonary Connection
Extra-Cardiac Fontan
5. Tricuspid Atresia
Classification
Type I (70%)
Normally related great vessels
Type II (30%)
D - transposition
Subsets
A - pulmonary atresia
B - pulmonary stenosis
C - normal pulmonary valve
Normal Vessels
Transposition
6. Clinical Diagnosis/Features
Cyanosis
Type IA, IB Tricuspid atresia
Some DILV
Congestive failure (subaortic stenosis)
Type IIC Tricuspid atresia
DILV
Balanced - mild cyanosis
Echocardiography very useful
Cardiac catheterization prior to operation
7. "Ideal" Fontan Candidate
Age > 2 years
LV morphology
Mean PAP < 15 mmHg
PVR < 2 units
Large unobstructed PAs
No ventricular hypertrophy
Normal ventricular function (EF > 50%)
LVEDP < 12mm Hg
8. Results of Definitive Surgery
Septation
Operative mortality = 30%
Heart block common
Rarely performed
Fontan
Operative mortality = 5%
15 year survival = 60-70%
Fenestrated Fontan
Operative mortality = 5%
Low morbidity
Extra-Cardiac Fontan
Operative mortality = 5%
Lower incidence arrhythmias
Cardiac transplantation
Operative mortality =10-15%
Functional results good
9. Fontan Physiology
RA pressure = 12-18 mmHg
Low systemic output
Pleural effusions common
Protein losing enteropathy = 5-10%
Long-term deterioration in ventricular function
10. Single ventricle anomalies - Summary Plan
0-6 months
Relief of CHF/cyanosis
PA banding, shunt
4-8 months
Bi-directional Glenn
Relief of subaortic stenosis
Relief of pulmonary artery distortion
12-24 months
Fenestrated Fontan or Fontan
Cardiac transplant for late failure of Fontan
