What is the treatment for right heart failure due to pulmonary hypertension?

Treatment for Right Heart Failure Due to Pulmonary Hypertension

The treatment of right heart failure due to pulmonary hypertension requires a comprehensive approach that includes general supportive measures, PAH-specific therapies, and management of right ventricular failure, with continuous intravenous epoprostenol being the preferred treatment for critically ill patients with advanced disease.

General Supportive Measures

Diuretics

• Diuretics are essential for managing right ventricular volume overload and should be used for symptomatic management of fluid retention 1
• Optimize diuretic dose in cases of progression of right heart failure in the post-operative period 1
• Monitor renal function and blood biochemistry to avoid hypokalaemia and pre-renal failure 1

Oxygen Therapy

• Supplemental oxygen is recommended to maintain oxygen saturation >90% at all times 1
• Particularly important for patients with WHO Functional Class III and IV with arterial blood O₂ pressure consistently <8 kPa (60 mmHg) 1

Anticoagulation

• Warfarin anticoagulation is recommended in all patients with idiopathic PAH based on retrospective observational studies 1
• Target INR ranges from 1.5-2.5 in North American centers to 2.0-3.0 in European centers 1
• Patients receiving long-term IV prostaglandins should be anticoagulated due to additional risk of catheter-associated thrombosis 1

Digoxin

• May be considered for patients with refractory right heart failure or atrial fibrillation/flutter to slow ventricular rate 1
• Short-term IV administration produces modest increase in cardiac output and reduction in circulating norepinephrine levels 1

PAH-Specific Therapies

Calcium Channel Blockers (CCBs)

• Only indicated for patients who demonstrate positive acute vasoreactivity testing 1
• High doses are required: nifedipine 120-240 mg/day, diltiazem 240-720 mg/day, or amlodipine up to 20 mg/day 1
• Close follow-up is essential to monitor both safety and efficacy 1
• If patient does not show adequate response (WHO-FC I or II with marked hemodynamic improvement), additional PAH therapy should be instituted 1

Prostacyclin Analogues

• Epoprostenol (IV): First-line therapy for WHO-FC IV patients and the preferred treatment for critically ill patients 1
• Only therapy for PAH shown to prolong survival in controlled studies 1
• Improves exercise capacity, hemodynamics, and survival in IPAH 1
• Treprostinil: Can be delivered via continuous IV or subcutaneous infusion 1
• Iloprost: Delivered by adaptive aerosolized device 6 times daily 1

Endothelin Receptor Antagonists (ERAs)

• Bosentan: Indicated for treatment of PAH to improve exercise ability and decrease clinical worsening 2
• Effective in WHO Functional Class II-IV symptoms 2
• Oral therapy that improves exercise capacity 1
• Requires monthly liver function test monitoring 1

Phosphodiesterase-5 (PDE-5) Inhibitors

• Improve exercise capacity and hemodynamics in PAH 1
• Sildenafil has shown favorable effects in PAH with relatively few minor side effects 1
• Can be used as replacement therapy when weaning from inhaled nitric oxide to prevent rebound pulmonary hypertension 1

Management of Right Ventricular Failure

Inotropic Support

• Dobutamine should be initiated in case of progression of right heart failure 1
• Preferred over milrinone due to shorter half-life when facing risk of hypotension 1
• Inotropes with neutral or beneficial effects on PVR include dobutamine, milrinone, and epinephrine 1
• Caution with dopamine: Higher mortality observed in patients with decompensated right heart failure receiving dopamine (60% vs 18%) 3

Advanced Therapies for Critical Illness

• Inhaled nitric oxide (iNO) can acutely decrease PVR and improve cardiac output 1
• Advantages: short half-life, quick onset of action, improves oxygenation, no detrimental effect on SVR 1
• Maintain systemic vascular resistance (SVR) greater than pulmonary vascular resistance (PVR) to prevent right ventricular ischemia 1
• Low threshold for admission to ICU/CCU for critically ill PAH patients 1

Ventilation Strategies (if required)

• Low-tidal volume strategy to minimize increases in RV afterload 1
• Keep peak pressures <30 cmH₂O 1
• Limit positive end-expiratory pressure to ≤10 cmH₂O if oxygenation allows 1
• Avoid permissive hypercapnea as acidosis can acutely increase PVR 1

Treatment Algorithm Based on WHO Functional Class

WHO-FC II or Early III:

1. Start with oral therapy: Endothelin receptor antagonists or PDE-5 inhibitors 1
2. Monitor response and consider combination therapy if inadequate response

WHO-FC III (Advanced) or IV:

1. Parenteral prostanoids (epoprostenol or treprostinil) as first-line therapy 1
2. Consider combination therapy if inadequate response
3. Evaluate for lung transplantation if progressive despite optimal medical management

Lung Transplantation

• Option for selected patients who progress despite optimal medical management 1
• 3 and 5-year survival after lung and heart-lung transplantation is approximately 55% and 45%, respectively 1
• Patients should be referred when they have an unacceptable response to PAH therapies 1

Pitfalls and Caveats

• CCBs should only be used in patients with positive vasoreactivity testing; inappropriate use can lead to severe side effects including hypotension 1
• Rebound pulmonary hypertension can occur upon weaning from inhaled nitric oxide 1
• Intubation can acutely decrease right ventricular preload and increase afterload, potentially causing sudden and irreversible hypotension 1
• Patients with PAH undergoing non-cardiac surgery should be managed in centers with appropriate expertise 1