Definitions
Abnormality of the formation of the pulmonary veins and their communication with the left atrium, resulting in abnormal return of pulmonary venous blood to the right atrium.
Pathophysiology
The pulmonary veins may feed directly into the right atrium or into vessels that connect to the right atrium, such as superior (SVC) or inferior (IVC) vena cavae
The abnormal communication of the pulmonary veins with roght atrium may occur above or below the diaphragm
Pulmonary venous return to the right atrium may be obstructed (commoner when communication is below the diaphragm) or unobstructed (commoner whrn communication occurs with the SVC)
Epidemiology
rare cardiac lesion accounting for less than 1% of all congenital heart disease
The below the diaphargm type has 4:1 male-to-female predominance
Atrial septal defect commonly occurs in association and allows mixed blood to flow from the right atrium, however, right ventricular hypertrophy and pulmonary oedema result.
Classification
TAPVC can occur with obstruction, which occurs when the anomalous vein enters a vessel at an acute angle and can cause pulmonary venous hypertension and cyanosis because blood cannot enter the new vein as easily.
Presentation
varies depending on the specific type of anomalous pulmonary return, particularly the presence or absence of pulmonary venous obstruction
- Non-obstructed type may present with murmur, mild cyanosis, and signs of CHF with right ventricular volume overload (eg. tachypnoea, poor feeding, failure to thrive, hepatomegaly)
- Obstructed type is dominated by cyanosis, poor cardiac output, and pulmonary edema, which develop early in the neonatal period
Investigation
ECG- may reveal RVH
CXR
- if pulmonary veins are obstructed, heart size is not enlarged but lung fields often reveal a “whiteout” due to severe pulmonary oedema
- non-obstructed: classic “snowman” appearance of the cardiac silhouette
Echo+doppler = diagnostic
Catheterization- useful in delineating mixed or more complex form of pulmonary venous abnormalities
MRI/CT - useful in complex forms of disease but has no role in the critically ill neonate or infant.
Management
- Critically ill, symptomatic pt (generally those with obstruction) require surgery
Surgical repair
- depends upon the defect, the goal is to redirect the anomalous pulmonary vein to the left atrium
- pre-op stabilization needs mechanical ventilation with high inspiratory pressure/positive end-expiratory pressure, as well as volume and inotropic support
Patients without obstruction- digoxin and diuretic therapy prior to surgery,
No benefit form prostaglandin E1- may induce pulmonary oedema due to increased pulmonary arterial flow
Prognosis & Complications
Pt maybe critically ill shortly after birth or develop symptoms in weeks to months
If surgical repair is timely, outcomes are good
Pt with delayed diagnosis or those who develop persistent pulmonary hypertension have a poorer prognosis
Abnormality of the formation of the pulmonary veins and their communication with the left atrium, resulting in abnormal return of pulmonary venous blood to the right atrium.
Pathophysiology
The pulmonary veins may feed directly into the right atrium or into vessels that connect to the right atrium, such as superior (SVC) or inferior (IVC) vena cavae
The abnormal communication of the pulmonary veins with roght atrium may occur above or below the diaphragm
Pulmonary venous return to the right atrium may be obstructed (commoner when communication is below the diaphragm) or unobstructed (commoner whrn communication occurs with the SVC)
Epidemiology
rare cardiac lesion accounting for less than 1% of all congenital heart disease
The below the diaphargm type has 4:1 male-to-female predominance
Atrial septal defect commonly occurs in association and allows mixed blood to flow from the right atrium, however, right ventricular hypertrophy and pulmonary oedema result.
Classification
- Supracardiac (50%): blood drains to one of the innominate veins (brachiocephalic veins) or the superior vena cava
- Cardiac (20%): blood drains into coronary sinus or directly into right atrium
- Infradiaphragmatic (20%): blood drains into portal or hepatic veins
- Mixed (10%)
TAPVC can occur with obstruction, which occurs when the anomalous vein enters a vessel at an acute angle and can cause pulmonary venous hypertension and cyanosis because blood cannot enter the new vein as easily.
Presentation
varies depending on the specific type of anomalous pulmonary return, particularly the presence or absence of pulmonary venous obstruction
- Non-obstructed type may present with murmur, mild cyanosis, and signs of CHF with right ventricular volume overload (eg. tachypnoea, poor feeding, failure to thrive, hepatomegaly)
- Obstructed type is dominated by cyanosis, poor cardiac output, and pulmonary edema, which develop early in the neonatal period
Investigation
ECG- may reveal RVH
CXR
- if pulmonary veins are obstructed, heart size is not enlarged but lung fields often reveal a “whiteout” due to severe pulmonary oedema
- non-obstructed: classic “snowman” appearance of the cardiac silhouette
Echo+doppler = diagnostic
Catheterization- useful in delineating mixed or more complex form of pulmonary venous abnormalities
MRI/CT - useful in complex forms of disease but has no role in the critically ill neonate or infant.
Management
- Critically ill, symptomatic pt (generally those with obstruction) require surgery
Surgical repair
- depends upon the defect, the goal is to redirect the anomalous pulmonary vein to the left atrium
- pre-op stabilization needs mechanical ventilation with high inspiratory pressure/positive end-expiratory pressure, as well as volume and inotropic support
Patients without obstruction- digoxin and diuretic therapy prior to surgery,
No benefit form prostaglandin E1- may induce pulmonary oedema due to increased pulmonary arterial flow
Prognosis & Complications
Pt maybe critically ill shortly after birth or develop symptoms in weeks to months
If surgical repair is timely, outcomes are good
Pt with delayed diagnosis or those who develop persistent pulmonary hypertension have a poorer prognosis
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