What is the treatment for a patient with a dilated right heart, dilated left atrium (LA), normal left ventricle (LV), preserved right ventricle (RV), moderate to severe tricuspid regurgitation (TR), mild mitral regurgitation (MR), and a high probability of pulmonary hypertension (PH)?

From the Guidelines

The treatment for dilated right heart with preserved right ventricular function, dilated left atrium, normal left ventricle, moderate to severe tricuspid regurgitation, mild mitral regurgitation, and high probability of pulmonary hypertension should prioritize tricuspid valve surgery, as indicated by the 2012 European Heart Journal guidelines 1.

Key Considerations

• The patient's condition, with moderate to severe tricuspid regurgitation and significant right heart dilation, suggests the need for surgical intervention to prevent irreversible right ventricular dysfunction.
• According to the guidelines, tricuspid valve surgery is indicated in patients with severe tricuspid regurgitation, and should be considered in patients with moderate primary tricuspid regurgitation, as well as in patients with mild or moderate secondary tricuspid regurgitation and significant dilatation of the annulus (≥40 mm) 1.
• The use of diuretics, such as furosemide or torsemide, can be useful for patients with severe tricuspid regurgitation and signs of right-sided heart failure, as recommended by the 2014 AHA/ACC guideline 1.

Treatment Approach

• Tricuspid valve surgery should be considered as the primary treatment option, given the patient's moderate to severe tricuspid regurgitation and preserved right ventricular function.
• Diuretics, such as furosemide (20-40mg daily) or torsemide (10-20mg daily), can be used to reduce fluid overload and relieve symptoms, as recommended by the 2014 AHA/ACC guideline 1.
• Pulmonary hypertension-specific therapy, such as phosphodiesterase-5 inhibitors (e.g., sildenafil or tadalafil), endothelin receptor antagonists (e.g., ambrisentan), or prostacyclin analogs, may be necessary to address the underlying pulmonary hypertension.
• Regular monitoring of renal function, electrolytes, and clinical response is essential, with echocardiographic follow-up every 3-6 months to assess treatment effectiveness.

From the FDA Drug Label

CLINICAL PHARMACOLOGY 12. 1 Mechanism of Action Sildenafil is an inhibitor of cGMP specific phosphodiesterase type-5 (PDE-5) in the smooth muscle of the pulmonary vasculature, where PDE-5 is responsible for degradation of cGMP. Sildenafil, therefore, increases cGMP within pulmonary vascular smooth muscle cells resulting in relaxation In patients with PAH, this can lead to vasodilation of the pulmonary vascular bed and, to a lesser degree, vasodilatation in the systemic circulation.

The treatment for dilated right heart, dilated LA, LV normal, RV preserved, moderate to severe TR, mild MR, and high probability of pulmonary hypertension may include sildenafil.

• Sildenafil is a PDE-5 inhibitor that can lead to vasodilation of the pulmonary vascular bed, which can help reduce pulmonary hypertension.
• The mechanism of action of sildenafil is to increase cGMP within pulmonary vascular smooth muscle cells, resulting in relaxation.
• However, it is essential to carefully consider the potential risks and benefits of using sildenafil in patients with certain underlying conditions, such as resting hypotension or severe left ventricular outflow obstruction 2.
• Additionally, sildenafil may worsen pulmonary veno-occlusive disease, and its safety is unknown in patients with bleeding disorders or active peptic ulceration 2.

From the Research

Treatment Options for Dilated Right Heart

• The treatment of significant tricuspid regurgitation (TR) is crucial, as it can lead to worsening prognosis regardless of the underlying etiology 3.
• In patients with pulmonary arterial hypertension (PAH) and secondary TR, anatomic and functional alterations in the right ventricle rather than the tricuspid valve are implicated in developing significant TR 4.
• Tricuspid annuloplasty with a ring should be performed at the initial mitral valve surgery, and the tricuspid annulus diameter (>or=3.5 cm) is the best criterion for performing the annuloplasty 5.

Factors Influencing Tricuspid Regurgitation Severity

• Pulmonary artery systolic pressure (PASP) is a strong determinant of TR severity, but many patients with pulmonary hypertension do not exhibit significant TR 6.
• Demographic characteristics, mechanical factors, remodeling of the right heart cavities, and other factors (possibly reflecting the presence of atrial fibrillation or occult organic TV disease) are predictive of TR severity 6.
• In patients with chronic mitral regurgitation, downstream pathologic changes can result in functional tricuspid regurgitation (FTR), and concomitant tricuspid valve repair at the time of mitral surgery is often recommended 7.

Transcatheter Therapies

• Transcatheter TV replacement and repair systems have shown efficacy and safety when used on the TV, providing an effective treatment option for patients not eligible for surgery 3.
• Advances in transcatheter therapies for the tricuspid valve and the evidence behind concomitant transcatheter tricuspid repair at the time of transcatheter mitral repair are being explored 7.