Partial Anomalous Pulmonary Venous Connection

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

• Young adult with dyspnea, recurrent respiratory infections, hemoptysis, and palpitations

• Physical findings of atrial septal defect (ASD):

  • – Right ventricular heave

  • – Systolic ejection murmur at the left sternal border

  • – Wide fixed split S₂ and a diastolic flow rumble over the tricuspid area

• Incomplete right bundle branch block on ECG

• Pulmonary vascular congestion, enlarged right heart, and occasionally evidence of the anomalous vein on chest radiograph

• Cardiac imaging evidence of anomalous pulmonary venous connection and ASD in many patients

GENERAL CONSIDERATIONS

• This condition is present in approximately 10% of patients with ASD (usually of the sinus venous type)

• Excessive pulmonary venous return to the right heart over years causes right atrial and ventricular dilation

• Atrial arrhythmias, right heart failure, and rarely pulmonary hypertension may develop

• Symptomatic patients or those with a large shunt (Qp/Qs ratio > 2.0) should have surgical repair, including repair of any associated congenital heart defects

• Surgical repair is contraindicated in patients with an associated ASD who have developed irreversible pulmonary vascular disease

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

• Dyspnea

• Signs of right heart failure

• Recurrent respiratory infections

• Hemoptysis

• Palpitations

PHYSICAL EXAM FINDINGS

• Right ventricular heave

• Systolic ejection murmur at the left sternal border

• Wide fixed split S₂ consistent with an associated ASD

• Diastolic flow rumble over the tricuspid valve

DIFFERENTIAL DIAGNOSIS

• Simple ASD

• Right heart failure from other causes

• Pulmonary hypertension from other causes

DIAGNOSTIC EVALUATION

LABORATORY TESTS

• No specific tests

ELECTROCARDIOGRAPHY

• Incomplete right bundle branch block

• Right-axis deviation

• Right ventricular hypertrophy

• Right atrial enlargement

IMAGING STUDIES

• Chest x-ray:

  • – Enlarged right atrium and right ventricle

  • – Pulmonary vascular congestion, rarely enlarged pulmonary vein

• Echocardiography:

  • – Enlarged right atrium and right ventricle, sometimes color-flow Doppler evidence of an ASD

  • – Transesophageal echocardiography can usually demonstrate anomalous drainage of 1 or more pulmonary veins into the right atrium (usually the right upper pulmonary vein)

  • – A sinus venous type ASD may be present at the junction of the superior vena cava and right atrium

DIAGNOSTIC PROCEDURES

• Cardiac catheterization:

  • – Oxygen saturation step-up in the right atrium (usually the high right atrium). Qp/Qs ratio may be calculated

  • – Pulmonary artery pressures are often elevated owing to increased pulmonary blood flow

  • – Pulmonary vascular resistance may be elevated

TREATMENT

CARDIOLOGY REFERRAL

• Signs and symptoms of right heart failure

• Suspected ASD and/or overwhelmingly positive agitated saline study

HOSPITALIZATION CRITERIA