Tricuspid valve disease

Tricuspid valve disease

Tricuspid valve disease is less common than aortic or mitral valve disease. Tricuspid regurgitation (TR) is more common than tricuspid stenosis.

Tricuspid stenosis¹²

Tricuspid stenosis is rare, occurring in less than 1% of patients with valvular heart disease and only 2.4% of all patients with tricuspid valve disease. More than 90% of patients with tricuspid stenosis have rheumatic heart disease.

In tricuspid stenosis, the tricuspid orifice becomes narrowed and obstructs blood flow from the right atrium to the right ventricle. The right atrium becomes hypertrophied, and right heart disease-induced heart failure develops without right ventricular dysfunction. The right ventricle remains underfilled and small.

The cause of tricuspid stenosis can be broadly classified into 3 categories:

• Acquired:

  • Rheumatic heart disease. By far the most common underlying cause, this is almost always associated with concomitant mitral stenosis.

  • Large infected vegetations.

  • Carcinoid syndrome.

  • Systemic disease such as systemic lupus erythematosus and antiphospholipid antibody syndrome, due to the associated risk of nonbacterial thrombotic endocarditis.

  • Hypereosinophilic syndrome.

  • Endomyocardial fibrosis.

  • Benign tumours, eg, atrial myxoma.

  • Metastatic disease, particularly of renal or ovarian origin.

• Congenital. This is very rare and usually associated with other cardiac abnormalities but is seen in:

  • Ebstein anomaly.

  • Fabry or Whipple diseases.

• Iatrogenic:

  • Permanent pacing or ICD leads can sometimes cause valvular stenosis, including tricuspid stenosis.

  • It is a rare complication of surgery for tricuspid regurgitation.

  • Appetite suppressant drugs (for example, fenfluramine, phentermine, and methysergide).

  • Microdosing of some psychedelic drugs, typically lysergic acid diethylamide (LSD), psilocybin and 3,4-Methylenedioxymethamphetamine (MDMA).³

Tricuspid stenosis symptoms and signs²

See also the separate Heart auscultation and Heart murmurs in children articles.

Detection requires careful evaluation, as it is almost always associated with left-sided valve lesions that dominate the presentation. Clinical signs are often masked by associated valve lesions, especially mitral stenosis.

• Low output symptoms of fatigue and weakness.

• Weight loss and reduced appetite.

• A sensation of a rapid neck pulse.

• Right hypochondrial discomfort from liver distension, hepatic pulsation, ascites, and peripheral oedema, which may be severe compared to the degree of dyspnoea.

• The lungs are usually clear in isolated tricuspid stenosis but there may be pulmonary oedema associated with concomitant mitral stenosis.

• There is often an opening "snap" followed by a middiastolic rumble. The murmur increases in intensity with inspiration or exercise.

• Raised jugular venous pressure.

Investigations²

• LFTs may be abnormal (mildly raised unconjugated bilirubin, alkaline phosphatase, or aminotransferases) due to hepatic congestion.

• ECG may show evidence of right atrial hypertrophy with tall peaked P waves; tall peaked T waves may be seen in leads II, III and aVF. Atrial fibrillation is seen in 50% of people with tricuspid stenosis.

• CXR may show a dilated right atrium without an enlarged pulmonary-artery segment.

• Echocardiography is the most useful test - to detect and quantify tricuspid stenosis and for assessment of the dimensions of cardiac chambers, determination of right ventricular and pulmonary pressures and detection of associated other heart valve abnormalities.

• Cardiac catheterisation: may be required prior to surgery to assess for possible coronary artery disease. Right heart catheterisation can help to determine the severity of the stenosis and associated congenital defects. Assessment of aortic and mitral valves via left heart catheterisation is useful in patients with rheumatic disease.

Tricuspid stenosis treatment and management²

Medical therapy

Diuretics may be useful in the presence of heart failure symptoms but are of limited long-term efficacy. They also risk reducing the preload too significantly.

Percutaneous valvotomy

This is offered to patients with unacceptable surgical risk and absence of tumour, thrombus, vegetation, and insignificant or mild tricuspid regurgitation.

Surgery
Surgery is offered to patients with low or moderate operative risk, and those with significant tricuspid regurgitation. Valvotomy is usually used in cases of isolated tricuspid stenosis but surgical repair or replacement is offered in cases of mitral valve involvement. Repair is recommended where possible but replacement may be performed if needed. No differences in long-term outcomes have been established between bioprosthetic and mechanical valve, although mechanical valves tend to be preferred in carcinoid syndrome.

The operative mortality for isolated tricuspid stenosis is significant and increases if performed with other valvular surgery (10% and 16%, respectively).

Prognosis

• Prognosis is generally good but dependent on the prognosis of the underlying disease, associated other heart abnormalities and associated arrhythmias.

Tricuspid regurgitation¹⁴⁵

Tricuspid regurgitation increases in incidence with age. The prevalence in the general population reaches 1.5% in men and 5.6% in women. Its prevalence is significantly higher among patients with left-sided valve disorders, particularly those with heart failure (HF), where it affects up to 23% of patients. In heart failure, tricuspid regurgitation is associated with a higher risk of mortality.

Tricuspid regurgitation can be characterised as primary (where an abnormality of the tricuspid valve is the cause) and secondary (where right atrial or ventricular dilatation is the cause):⁶

Causes of tricuspid regurgitation⁵

Primary tricuspid regurgitation:

• Congenital:

  • Ebstein's anomaly.

  • Connective tissue disorders, such as Marfan's or Ehlers-Danlos syndrome.

  • Giant right atrium.

  • Tricuspid valve malformations.

• Acquired:

  • Infective endocarditis.

  • Iatrogenic (caused by permanent pacemaker or implantable cardioverter-defibrillator lead placement or removal).

  • Traumatic.

  • Rheumatic valve disease.

  • Carcinoid syndrome.

  • Myxomatous degeneration.⁷

  • Endocarditis due to systemic lupus erythematosusor rheumatoid arthritis.

  • Endomyocardial fibrosis.

  • Drug-induced disease (the same drugs that can cause tricuspid stenosis can cause tricuspid regurgitation.

Secondary tricuspid regurgitation:

This is more common and the tricuspid valve is usually normal but regurgitation is caused by right atrial or ventricular dilatation due to:

• Left-sided heart disease: Left ventricular dysfunction or left-sided valvular heart disease resulting in pulmonary hypertension.

• Pulmonary hypertension: Cor pulmonale, pulmonary embolism, pulmonary hypertension of any cause left to right shunt.

• Right atrial abnormalities: Atrial fibrillation.

• Stenosis of the pulmonic valve or pulmonary artery.

• Hyperthyroidism.

Tricuspid regurgitation symptoms and signs⁵

See also the separate Heart auscultation and Heart murmurs in children articles.

• Clinical features of right sided heart failure including dyspnoea, fatigue, cyanosis, cold skin, oedema, and discomfort in the right hypochondrium.

• Exercise intolerance.

• Distended and pulsatile jugular vein.

• Jugular venous pressure is elevated with a prominent systolic 'v' wave.

• High-pitched pansystolic murmur, most prominent in the fourth intercostal space in the left parasternal region. The murmur is accentuated during inspiration, with exercise, with legs raised, and with direct liver compression.

Investigations⁵⁸

• Abnormal LFTs may be present.

• ECG: findings are usually nonspecific; they may show right atrial hypertrophy (tall peaked 'p' waves), incomplete right bundle-branch block, Q waves in lead V1, and atrial fibrillation. Right axis deviation may be present.

• CXR: shows marked cardiomegaly with right heart enlargement, and pleural effusions. Ascites with diaphragmatic elevation may be present. Pulmonary arterial and venous hypertension are common.

• Echocardiography: to detect and quantify tricuspid regurgitation and for assessment of the dimensions of cardiac chambers, determination of right ventricular and pulmonary pressures and detection of other associated heart valve abnormalities.

• Cardiac catheterisation: may be required prior to surgery to assess for possible coronary artery disease and help determine the severity of the regurgitation and associated congenital defects.

Tricuspid regurgitation treatment and management⁵⁹

Medical therapy

• Diuretics are useful in the presence of right heart failure. ACE inhibitors can also be helpful.

• Treatment of pulmonary hypertension may be indicated.

• Rhythm control may help to decrease tricuspid regurgitation and contain annular dilatation in patients with chronic atrial fibrillation.

Surgery
Tricuspid valve repair should be performed during left-sided surgery in patients with severe tricuspid regurgitation and for patients with mild-moderate tricuspid regurgitation and either dilatation of the tricuspid annulus or a previous history of right-sided heart failure.¹⁰

In endocarditis, the tricuspid valve is recommended to be removed and not immediately replaced. In those with carcinoid, a mechanical valve is preferred over a bioprosthesis.

Prognosis

• Severe tricuspid regurgitation has a poor prognosis, even if it may be well tolerated functionally for years.

• Severe tricuspid regurgitation has been found to be a strong predictor of prognosis in various disease states.⁴

• Patients with moderate or severe tricuspid regurgitation have increased mortality, with an observed survival of 10.2% at 15 years, with the highest mortality in patients with tricuspid regurgitation associated with left-sided heart disease. However, even in patients with isolated tricuspid regurgitation, the yearly mortality rate is 12.1%.¹¹

• Isolated tricuspid valve repair has a mortality of 10% though this may be due to delays in treatment.⁴

Tricuspid atresia¹²

Tricuspid atresia is a rare congenital cyanotic heart disease caused by the complete agenesis of the tricuspid valve. Presentations vary due to differences in the extent of pulmonary blood flow. It is caused by abnormal heart development during embryogenesis without an underlying genetic predisposition.

Tricuspid atresia symptoms¹²

• Most cases are diagnosed prenatally in MEDCs.

• Tricuspid atresia is usually detected in infancy with cyanosis, heart failure and growth restriction.

• Cardiac murmurs are often present:

  • A pansystolic murmur, which may signify blood flow through the ventricular septal defect.

  • Systemic-to-pulmonary arterial collaterals or arterial-to-pulmonary arterial anastomoses surgically created to improve pulmonary blood flow, which may cause a continuous murmur.

  • A murmur indicating mitral regurgitation, which may be present.

• Older patients may have clubbing.

• Babies with a VSD and without pulmonary stenosis do not present with cyanosis and therefore may initially go undiagnosed. They tend to present with signs and symptoms of heart failure, such as tachypnoea or respiratory distress, poor feeding, and impaired growth. Notable findings upon physical examination include tachypnoea, tachycardia, and hepatomegaly.

Investigations

• CXR: cardiomegaly is usually present, with a prominent right heart border (enlargement of the right atrium). Pulmonary vascular markings are usually diminished (but may be increased when pulmonary flow is not obstructed).

• Other investigations include ECG, echocardiography, and cardiac catheterisation.

Tricuspid atresia treatment and management¹²¹³¹⁴

• Infants with obstructed pulmonary blood flow and severe hypoxaemia require urgent prostaglandin E infusions in order to maintain patency of the ductus arteriosus.

• Other non-surgical management includes oxygen therapy, prevention of bacterial endocarditis, and management of heart failure.

• Most patients with tricuspid atresia require some form of surgical treatment during the first year of life; there are normally 2-3 stages of surgical management, ending in the definitive Fontan procedure.

Complications

• Paradoxical emboli, stroke, brain abscess.

• Polycythaemia.

• Progressive cardiac dilatation.

• Ventricular dysfunction.

• Mitral valve insufficiency.

• Arrhythmias.

Prognosis

Patients who do not have surgery have a high mortality in the first year of life. With surgical interventions, the majority survive well into adulthood. The operative mortality is consistently less than 2%. Recent studies have shown a transplant-free survival rate of 92% at 15 years.¹⁵