Total Anomalous Pulmonary Venous Connection

Seoul National University Hospital

Department of Thoracic & Cardiovascular Surgery

Total Anomalous Pulmonary Venous Connection

Seoul National University Hospital

Department of Thoracic & Cardiovascular Surgery

Total Anomalous Pulmonary Venous Connection

Definition Cardiac malformation in which there is no direct connection between any pulmonary vein & left atrium, but all the pulmonary veins connect to right atrium or one of it’s tributaries. A PFO or an ASD is present essentially all persons who survive after birth.

History Wilson : 1st description in 1798 Muller : 1st closed partial approach in 1951 Lewis & Varco : Successful open repair in 1956

Total Anomalous Pulmonary Venous Connection

Origin of anomalous connection 1. Drainage to right atrium 2. Drainage to right common cardinal system (SVC or azygous vein) 3. Drainage to left common cardinal system (Left innominate vein or coronary sinus) 4. Drainage to umbilical-vitelline system (Portal vein, ductus venosus, and so on)

Pulmonary Vein

Splanchnic plexus provides drainage of the lung buds into cardinal & umbilicovitelline venous system. Common pulmonary vein evaginates

from the left atrium and merges with the splanchnic plexus. Connections of pulmonary drainage to systemic venous system regress.

Development

TAPVCPathophysiology• Entire pulmonary venous return drains into the rig

ht atrium, usually via a common pulmonary vein confluence, resulting in complete pulmonary and systemic venous mixing.

• Oxygenated blood reaches the left heart via an inter-atrial connection (i.e.,ASD, PFO).

• Mechanical or functional obstruction of the pulmonary venous return leads to cyanosis, acidosis, pulmonary hypertension, & congestion.

TAPVC

1. Pulmonary venous anatomy 1) Type : Supracardiac 45%

Cardiac 25%

Infracardiac 25%

Mixed 5%

2) Pulmonary venous obstruction

. Junction of connecting vein

or compression, or long

narrow connect vein

. Functional obstruction

(restrictive PFO)

2. Chamber & septal anatomy . LA & LV : small

. ASD or PFO : small in 1/2,

rarely no ASD or PFO

3. Pulmonary vasculature . Increased arterial muscularity

. Structural change

4. Associated condition . PDA : 15%

. VSD : occasionally

. TOF, DORV, IAA : rarely

Morphology

TAPVCTypes

TAPVCTypes

Supracardiac TAPVC

Common vein

Connecting vertical vein

Cardiac Type TAPVC

Common vein

TAPVCClinical features & diagnosis 1. Presentation . Critically ill infants during 1st few week of life . Unexplained tachypnea & unimpressive cyanosis . Metabolic acidosis : pulmonary venous obstruction 2. Examination . No particularly overactive heart & unimpressive heart sound 3. Chest radiography . Normal heart size with diffuse haziness or ground glass if pulmonary venous obstruction . Large heart size with high pulmonary blood flow . Figure of 8, snowman configuration 4. Echocardiography 5. Cardiac catheterization & cineangiography

TAPVCNatural history 1. Incidence . Relatively uncommon anomaly, 1.5~3% of CHD

2. Survival . Unfavorable prognosis

50% survival in 3months

20% survival in one year

. Usually have pulmonary venous obstruction due to

long pulmonary venous pathway & a small PFO

. Those who survive the first year of life usually have

large ASD, no pulmonary venous obstruction

TAPVC

Indications for operation• Investigation must be undertaken promptly in any neonate or infant, no matter how young, who develops signs or symptoms suggestive of TAPVC

• Immediate operation in any neonate or infant whom are importantly ill with TAPVC• Prompt operation in any 6-12 months old infant• Advisable if severe pulmonary vascular disease has not developed in old patients (under 8 units)

TAPVCOperative techniques• Operation should be undertaken as an emergency after

diagnosis by echocardiography who enter the hospital

critically ill. Preoperative preparation & stabilization

is contraindicated. 1. TAPVR to Lt. innominate vein 2. TAPVR to SVC 3. TAPVR to coronary sinus 4. TAPVR to right atrium 5. TAPVR to infradiaphragmatic vein

TAPVCSupracardiac type

TAPVCCardiac type

TAPVCInfracardiac type

• Suturelesstechnique for the relief of PV stenosis. A, Theincision is made into the left atrium and extended into both upper and lower PVostia separately. B, Suturing is begun in thepericardium just above the junction of the superior PV with the left atrium. C, A second inferior suture is started below theinferior PV and continued in the same manner to the left atrial incision to jointhe superior suture line.

Sutureless technique

TAPVC

Primary Sutureless RepairRationale• Small size of the pulmonary vein is a major risk factor for la

ter development of PVS after conventional TAPVD repair and that high mortality of right atrial isomerism is related, at least in part, to intrinsically small pulmonary veins.

• Furthermore, most of the patients with RAI are not anatomic candidates for biventricular repair. PVS is a risk factor for poor Fontan operation outcome

• The acute anatomic benefit for the sutureless repair is that each vein is its own native size, without any suture material to cause an excessive inflammatory reaction or luminal compromise

TAPVC

1. Survival

2. Modes of death

. Hypertensive crisis

. Pulmonary venous stenosis

3. Incremental risk factors

for death

. Infracardiac drainage

. Pulmonary venous obstruction

. Poor preoperative state

. Small size of pulmonary vein

. Increased PVR

. Small left ventricle

4. Functional status

5. Hemodynamic result

6. Cardiac rhythm 7. Reoperation

. Anastomotic stricture

(5~10%)

. Pulmonary vein stenosis

Surgical results

TAPVCSpecial situation & controversies 1. Delayed operation In critical patients with obstruction at atrial level, balloon dilation and 1-2 days later operation

2. Mixed total anomalous venous connection 3. Operative exposure 4. Surgical enlargement of left atrium Decrease in atrial volume of more than 50% result in reduction in cardiac output ?

5. Pulmonary vein stenosis

Residual TAPVC

PVD in remained anomalous veins• Possible pressure-sensitive receptors at

the anomalous vein-vena cava junction

• Axon reflex triggered by right atrial

distention

• Results of the increased blood flow

Pulmonary Vein Stenosis

Etiology 1. Low grade venous obstruction presents at the

end of procedure results in reactive fibrosis

( diffuse fibrosis & thickening of vein )

2. Self perpetuating stenosis

3. Intraatrial thickening

4. Diffuse pulmonary vein stenosis

5. Congenital nature ( hypoplasia, focal stenosis,

discrete ostial stenosis)

Pulmonary Vein Stenosis

Factors of development 1. Small confluent pulmonary vein

2. Suture material

3. TAPVC type?

4. Undue trauma toward pulmonary

vein ostium and tension

5. Steroid therapy

Congenital PV Stenosis

Clinical features• Occur in about 0.4% of congenital heart defects and one or

multiple veins may be affected. • Histologically, the lesion is characterized by fibrous intimal

thickening in most cases and medial hypertrophy in many • The first surgical repair of congenital PV stenosis was repor

ted by Kawashima and colleagues in 1971 and surgical approaches have evolved over the years, but results have been generally disappointing.

• Diffuse restenosis has been documented as a significant cause of late mortality after repair

Acquired PV Stenosis

Characteristics• Anatomically localized to the anastomosis, and the natur

al history is more favorable, or the stenosis may extend diffusely into the branch pulmonary veins.

• It can sometimes be difficult to distinguish these forms of acquired PV stenosis at the time of presentation.

• Acquired PV stenosis occurs in approximately 7% to 11% of early survivors after total anomalous pulmonary venous connection repair

• Results of repair of acquired PV stenosis have also been less than optimal due to the problem of restenosis

Acquired PV Stenosis

Anatomic features• Post-repair pulmonary vein stenosis appears to have three

basic subtypes. • The most minimal form of the disease is limited to the anast

omotic area with sparing of the pulmonary veins and confluence, suggesting a technical error or imperfection at the time of initial repair.

• The intermediate form is limited to the pulmonary venous confluence in addition to the anastomotic area.

• The most extensive form of the disease includes a fibrous reaction extending retrograde deep into the lung parenchyma.

Pulmonary Vein Stenosis

Strategy for treatment 1. Minimize trauma at suture line Suture line (tension or inflexibility, deformation) Suture material Handling the vein tissue 2. Avoid postoperative turbulence Constraints imposed by restrictive characteristics 3. Surgical methods Operative patch venoplasty Sutureless pericardial marsupializationSutureless pericardial marsupialization Catheter dilation Stent placement and combination

Complex TAPVC

Etiology of high mortality 1. The interplay of systemic shunt with abnormal pulmonary vasculature contributes to difficulty in maintaining postoperative pulmonary to systemic flow ratio. 2. To limit excessive pulmonary blood flow with banding, or augmentation with shunt, the end result is similar. 3. The static matching of this resistance to the cardiac output in face of abnormal pulmonary vasculature may not allow appropriate regulation of pulmonary blood flow during dynamic changes.