Pulmonary Valve Regurgitation

Key Features

Essentials of Diagnosis

• Most cases are due to pulmonary hypertension resulting in high-pressure pulmonary valve regurgitation

• Echocardiogram is definitive in high-pressure pulmonary valve regurgitation but may be less definitive in low-pressure regurgitation

• Loud diastolic (Graham–Steell) murmur in high-pressure pulmonary valve regurgitation

• Soft or no murmur in low-pressure pulmonary valve regurgitation

• Low-pressure pulmonary valve regurgitation is well tolerated

General Considerations

• Can be divided into high-pressure and low-pressure causes

• High-pressure causes are due to pulmonary hypertension

• Low-pressure causes usually due to

  • A dilated pulmonary annulus

  • A congenitally abnormal (bicuspid or dysplastic) pulmonary valve

  • Plaque from carcinoid disease

  • Surgical pulmonary valve replacement or the residual from a surgical transannular patch used to reduce the outflow gradient in tetralogy of Fallot

• Because the right ventricle (RV) tolerates a volume load better than a pressure load, it tends to tolerate low pressure pulmonary valve regurgitation for long periods of time without dysfunction

Clinical Findings

• Most patients are asymptomatic; those with marked PR show symptoms of right heart volume overload

• A hyperdynamic RV can usually be palpated

• If the pulmonary artery (PA) is enlarged, it may be palpated along the left sternal border

• P₂ will be palpable in pulmonary hypertension and both systolic and diastolic thrills are occasionally noted

• In high-pressure pulmonary valve regurgitation, a loud diastolic murmur, often due to a dilated pulmonary annulus, increasing with inspiration and decreasing with Valsalva maneuver

• The second heart sound may be widely split due to prolonged RV systole or associated right bundle branch block

• A pulmonary valve systolic click may be noted as well as a right-sided gallop

• If pulmonary valve stenosis is also present, the ejection click may decline with inspiration while any associated systolic pulmonary murmur increases

Diagnosis

Imaging Studies

• The chest radiograph may show only the enlarged RV and PA

• Echocardiography may demonstrate

  • Evidence of RV volume overload (paradoxic septal motion and an enlarged RV)

  • Peak systolic RV pressure

  • Any associated tricuspid regurgitation

  • Size of PA

• Cardiac MRI and CT can be useful for

  • Assessing the size of the PA

  • Estimating regurgitant flow

  • Excluding other causes of pulmonary hypertension (eg, thromboembolic disease, peripheral PA stenosis)

  • Evaluating RV function

Diagnostic Studies

• ECG is generally of little value except that

  • A right bundle branch block is common

  • ECG criteria for right ventricular hypertrophy (RVH) may be present

• At times, only contrast angiography or MRI of the main PA will show the free-flowing regurgitation in low-pressure regurgitation

• Cardiac catheterization is confirmatory only

Treatment

• Specific therapy other than treatment of the primary cause rarely needed

• In high-pressure pulmonary valve regurgitation, controlling the cause of the ...