Pulmonary Regurgitation

Pulmonary regurgitation (PR) is diastolic backflow of blood from the pulmonary artery into the right ventricle.

Commonest cause is repaired congenital heart disease, particularly tetralogy of Fallot after transannular patch repair, and after balloon or surgical pulmonary valvotomy for stenosis.

Other causes: pulmonary hypertension (Graham Steell murmur), dilated pulmonary artery (idiopathic, Marfan), endocarditis, carcinoid, rheumatic, drug induced, congenital absence of the valve.

Mild physiological PR is common in healthy people.

Chronic severe PR causes right ventricular volume overload, dilatation, dysfunction, tricuspid regurgitation, atrial and ventricular arrhythmia, sudden death. Tolerated for decades before decompensation.

• Often asymptomatic for years. Later exercise intolerance, dyspnoea, fatigue, palpitations, syncope, right heart failure.
• Soft, low pitched early diastolic decrescendo murmur at the left upper sternal border, increasing with inspiration; right ventricular heave; wide split S2.
• In pulmonary hypertension, a high pitched Graham Steell murmur with loud P2.
• Ventricular tachycardia in repaired Fallot is a risk marker (QRS duration over 180 ms).

• Echocardiography: jet width, short pressure half time, diastolic flow reversal in the branch pulmonary arteries, right ventricular size and function.
• Cardiac MRI is the gold standard: regurgitant fraction (over 40% severe), right ventricular end diastolic volume index, ejection fraction.
• ECG: QRS duration (over 160 to 180 ms predicts arrhythmia), right bundle branch block.
• Cardiopulmonary exercise testing; Holter monitoring.
• CT or catheterisation for anatomy (branch stenosis, right ventricular outflow tract, conduit).

• Mild to moderate PR: observation, MRI every 2 to 3 years in repaired Fallot.
• Treat contributing conditions: residual branch pulmonary stenosis, pulmonary hypertension (pulmonary vasodilators when indicated), endocarditis.
• Heart failure: diuretics (furosemide 20 to 80 mg), spironolactone.
• Pulmonary valve replacement (surgical bioprosthesis or transcatheter Melody or Sapien valve) for severe PR with symptoms, or asymptomatic with right ventricular end diastolic volume index over 150 to 160 mL/m2, end systolic volume index over 80 mL/m2, right ventricular ejection fraction below 47%, QRS over 160 ms, sustained arrhythmia, or progressive tricuspid regurgitation.
• Transcatheter replacement requires a suitable landing zone (conduit or bioprosthesis); percutaneous options exist for native outflow tracts.
• Arrhythmia: amiodarone, ablation, ICD for ventricular tachycardia or risk stratification by electrophysiology study.
• Endocarditis prophylaxis for prosthetic valve and unrepaired cyanotic disease; adult congenital heart disease clinic follow up.
• Exercise: avoid competitive sports in severe disease.