SINGLE VENTRICLESSINGLE VENTRICLES

Perils Perils of of

Imperfect Imperfect PlumbingPlumbing

R. Dennis Steed, MDAssociate ProfessorDepartment of PediatricsDivision of Pediatric CardiologyEast Carolina University – Brody School of MedicineGreenville, NC

Single VentriclesSingle VentriclesAnatomical SubstratesAnatomical Substrates

• Atresia / hypoplasia of valvesAtresia / hypoplasia of valves

• Double inlet ventriclesDouble inlet ventricles

• Severely unbalanced AV canal defects Severely unbalanced AV canal defects with complex attachmentswith complex attachments

• Atrial isomerism / heterotaxyAtrial isomerism / heterotaxy

TRICUSPID ATRESIA

1.5 : 1

Single VentriclesSingle VentriclesNorwood ProcedureNorwood Procedure

• Neonatal open procedureNeonatal open procedure

• First week of lifeFirst week of life

• Reconstruction of aorta using pulmonary Reconstruction of aorta using pulmonary artery and placement of BT shuntartery and placement of BT shunt

Stage I Norwood with Sano Stage I Norwood with Sano ModificationModification::

Single VentriclesSingle VentriclesGlenn Shunt / Hemi - Glenn Shunt / Hemi - FontanFontan

• 6 - 9 months6 - 9 months• • volume unloads ventriclevolume unloads ventricle

• addresses any pulmonary artery distortionaddresses any pulmonary artery distortion

• perceived decrease in pleural effusionsperceived decrease in pleural effusions

• facilitates completion of Fontanfacilitates completion of Fontan

Single VentriclesSingle VentriclesFontan ProcedureFontan Procedure

• Generally done at 2 - 4 years of ageGenerally done at 2 - 4 years of age

• Intra-atrial baffle of inferior vena caval blood to Intra-atrial baffle of inferior vena caval blood to pulmonary arterypulmonary artery

• Common to use fenestrationCommon to use fenestration

• Extracardiac conduit of inferior caval blood to Extracardiac conduit of inferior caval blood to pulmonary arterypulmonary artery

Single VentriclesSingle VentriclesFontan ProcedureFontan Procedure

Key Components of Favorable Post-Fontan Hemodynamics:

1.Normal ventricular function (systolic and diastolic)

2.Lack of important A-V valve incompetence.

3.Low trans-pulmonary gradient.

Evaluation of Systolic Ventricular function in Univentricular Hearts:

Use a method that is reproducible to allow for serial comparisons

Evaluation of Systolic Ventricular function in Univentricular Hearts:

Left ventricular morphology: routine ejection indices for your lab.

Right ventricular morphology: Mid cavitary two-dimensional area shortening may be most reliable.

Evaluation of Diastolic Ventricular function in Univentricular Hearts:

1.E:A ratios.

2.May use IVRT with ventricles of left ventricular morphology (sufficient proximity between the aortic valve and a A-V valve.

Trans-pulmonary Gradient:

1.Ideal: 3- 5 mm Hg

2.Satisfactory: 6-8 mm Hg