One & A Half Ventricle Repair

Seoul National University Hospital

Department of Thoracic & Cardiovascular Surgery

One & A Half Ventricle Repair

• Rationale

In an attempt to avoid the high early mortality and extending the limits of biventricular repair for patients with borderline pulmonary ventricle, or late complications after Fontan operation while still achieving separate pulmonary and systemic circulation

Introduction

• Long-term outcomes of the Fontan procedure have been less ideal.

• Late problems of ventricular hypertrophy, dilation, and eventual failure are time-dependant and appear to be inevitable.

• Avoidance of the Fontan physiology is preferred.

• At the same time, biventricular repair in patients with borderline(inadequate) pulmonary ventricles can result in poorer early and late survival.

• One and a half ventricle repair would be logical if it improves patient survival and functional status.

One & A Half Ventricle Repair

• Term A superior vena cava to pulmonary artery anastomosis

can be created as an adjunct to biventricular repair.

• Aim

By diverting the superior vena caval flow directly to the lun

gs, pulmonary ventricular volume load is reduced by appr

oximately one third.

Inappropriate Pulmonary Ventricle

1. Small tricuspid annulus . Less than 75% of the diameter of IVC . Tricuspid z-value less than –2 . Pulmonary ventricular volume less than 70~ 80% 2. Normal or dilated tricuspid valve annulus . Hypertrophic RV exposed to long-lasting hypertension & cyanosis . Dilated RV & poorly contracting due to chronic PR 3. A pulmonary ventricle, guarded by a AV valve, even if hypoplastic or diminutive

Anatomic Selection Criteria for Small Pulmonary Ventricle

Tricuspid Pulmonary Operation

z-Value Ventricular

Volume

> -2 > 80% Biventricular repair

< -2 < 80% 1 ½ repair & CPA

< -5 < 50% 1 ½ repair & CPA

Atrial fenestration

< -10 ? < 30% Fontan operation

Principles of Partial Biventricular Repair

1. To create a modified in-series circulation with

no left-to-right, or right-to-left shunting

2. Systemic ventricle pumping a single cardiac

output

3. Pulmonary circulation receiving full cardiac

output through the pulmonary ventricle &

superior cavo-pulmonary connection

Advantages of Partial Biventricular Repair

1. The Fontan operation remains a suboptimal form

of definite palliation.

2. Maintenance of equal and separate pulmonary &

systemic circulation

3. Incorporating the pulmonary ventricle into the

circulation with a reduced volume load

4. Exercise tolerance, rhythm status comparing the

Fontan procedure, & effect of cerebral function of

pulsatile & mildly elevated pressure in SVC

Indications for Partial Biventricular Repair

1. Small physiologic right ventricle

2. Acute & chronic right ventricular dysfunction

3. Facilitation of biventricular repair without

hypoplasia or functional impairment of the

pulmonary ventricle

4. Simplifying the operation requiring a complex

intraatrial baffle for atrial isomerism, single atrium

& bilateral SVC

Decisions for Biventricular or One & a Half Ventricular Repair

1. Influencing factors for biventricular repair 1) Size of ventricle 2) Morphology of ventricle 3) Function of ventricle 4) Demensions and function of the inflow and outflow

2. Indications for one and a half ventricular repair 1) Small right ventricle 2) Chronic right ventricular dysfunction 3) Acute right ventricular dysfunction 4) Facilitation of repair without hypoplasia or functional impairment of pulmonary ventricle

Decision Making for Pulmonary Ventricles

• Assessing pulmonary ventricular morphology

Missing or defective component of right ventricle

Measurement of ventricular volume (Simpson method)

The tricuspid annulus

• Functional assessment of pulmonary ventricle

Functional analysis of right ventricle by Echo, Angio, MRI

Ventricular wall thickness & diastolic filling

Dilated ventricle

• Pulmonary afterload

Elevated PVR is not indicated.

Simplified Physiologic Indications (Mavroudis, 1999)

• Volume unloading

• Reduced ventricular contraction

• Correction of cyanosis (LSVC to LA)

• Pressure considerations

One & a Half Ventricle Repair

• Atrial isomerism complex• AVSD with or without TOF• Atrioventricular & ventriculoarterial discordance• Double-inlet left ventricle• Double-outlet right ventricle• D-transposition of great arteries• Ebstein’s anomalies• Pulmonary atresia with intact ventricular septum• Pulmonary stenosis• Tetralogy of Fallot• VSD with or without straddling atrioventricular valves

One & a Half Ventricle Repair

• Arterial Switch Operation , VSD closure and BCPC in patient with TGA, VSD , small RV cavity

Arterial Switch Operation

One & a Half Ventricle Repair

• Arterial Switch Operation , VSD closure and BCPC in patient with TGA, VSD , small RV cavity

BCPC

small RV

Intermediate Outcomes

• Rare complications of Fontan operation

Atrial arrhythmia

Ventricular failure

Pulmonary arteriovenous fistula

Protein losing enteropathy

• Presence of additional pulmonary blood flow

Prolonged pleural effusion or chylothorax

Limited morning periorbital edema

Pseudoaneurysm of SVC

Pulmonary regurgitation & excessive pulsatility