Chronic Right Heart Failure

Chronic right heart failure is the long term inability of the right ventricle to maintain output at normal venous pressures. It produces systemic venous congestion (oedema, ascites, hepatic and renal congestion) and reduced exercise capacity and is a powerful predictor of mortality.

The commonest cause is left heart disease (left sided failure and mitral valve disease). Others are pulmonary arterial hypertension, chronic thromboembolic pulmonary hypertension, chronic lung disease (cor pulmonale from COPD, interstitial disease, obstructive sleep apnoea and obesity hypoventilation). Further causes are congenital heart disease (Ebstein anomaly, repaired tetralogy of Fallot, Eisenmenger syndrome, systemic right ventricle), tricuspid and pulmonary valve disease, right ventricular cardiomyopathy and constrictive pericarditis.

Schistosomiasis, rheumatic heart disease and endomyocardial fibrosis are regionally important causes in sub-Saharan Africa.

Pathophysiology.

Persistent pressure or volume overload causes right ventricular hypertrophy then dilatation, tricuspid annular dilatation and functional tricuspid regurgitation, and neurohormonal activation that retains salt and water.

Raised right atrial pressure impairs venous return from the liver and kidney: congestive hepatopathy (cholestatic liver tests, cardiac cirrhosis) and cardiorenal syndrome result. Gut oedema causes protein losing enteropathy and malabsorption.

Septal shift reduces left ventricular filling, and ventricular interdependence lowers systemic output.

Fatigue, exertional dyspnoea, abdominal distension, right upper quadrant discomfort, early satiety, peripheral oedema and exertional syncope. Signs: raised jugular venous pressure with prominent v waves, parasternal heave, loud pulmonary component of the second sound, right sided third heart sound, tricuspid regurgitation murmur, pulsatile hepatomegaly, ascites, and cyanosis in shunt lesions.

• ECG: right axis deviation, right ventricular hypertrophy, P pulmonale, right bundle branch block, atrial arrhythmia.
• Echocardiography: right ventricular size and function (TAPSE under 17 mm, tricuspid S' under 9.5 cm/s, fractional area change under 35%), right atrial area, tricuspid regurgitation velocity, estimated pulmonary pressure, inferior vena cava size, pericardial effusion, and septal shape.
• Cardiac MRI: right ventricular ejection fraction (under 45% abnormal), volumes, scar and shunt quantification.
• Right heart catheterisation to define pulmonary hypertension: mean pulmonary artery pressure over 20 mmHg; pre-capillary disease has pulmonary artery wedge pressure of 15 mmHg or less and pulmonary vascular resistance over 2 Wood units.
• NT-proBNP (risk bands for pulmonary arterial hypertension: under 300 ng/L low, 300 to 1100 intermediate, over 1100 high), six minute walk distance (over 440 m low risk, 165 to 440 intermediate, under 165 high).
• Blood gas, spirometry and lung volumes, ventilation perfusion scan for chronic thromboembolic disease, high resolution CT, sleep study, HIV and schistosomiasis serology where relevant, liver and renal tests.
• Congenital heart disease assessment with echocardiography and MRI.

Differential diagnosis.

• Left heart failure and valvular disease with secondary pulmonary hypertension.
• Constrictive pericarditis and restrictive cardiomyopathy.
• Primary liver disease or nephrotic syndrome (ascites and oedema without raised venous pressure).
• Superior or inferior vena cava obstruction and hepatic vein occlusion.

Treat the underlying cause (the main determinant of outcome): correct left sided and valvular disease, shunts and obstructions, treat sleep apnoea and hypoventilation, optimise chronic lung disease, and treat thromboembolic disease.

Decongestion.

• Furosemide 40 to 120 mg orally once or twice daily (maximum 240 mg in a single dose in refractory disease under specialist care).
• Alternatively, torsemide 20 to 100 mg daily, or bumetanide 1 to 5 mg daily. Titrate to dry weight, aiming for weight loss of 0.5 to 1 kg daily when overloaded. Gut oedema reduces oral absorption, so use intravenous diuretics when oral therapy fails.
• Add spironolactone 25 to 100 mg orally once daily (potassium under 5.0 mmol/L, eGFR over 30; check at 1 week and 4 weeks) for hepatic congestion and ascites. Alternatively, acetazolamide 250 to 500 mg daily, or metolazone 2.5 to 10 mg daily in short courses, with daily electrolytes.
• Sodium restriction to about 2 g daily and fluid restriction of 1.5 to 2 litres daily if hyponatraemic. Avoid over diuresis because the right ventricle is preload dependent.
• Large volume paracentesis with albumin 6 to 8 g for each litre removed when ascites is tense.

Pulmonary arterial hypertension (group 1) treatment (specialist centre, risk directed; initial combination therapy is usual):

• Tadalafil 20 mg orally once daily increased to 40 mg once daily, or sildenafil 20 mg three times daily; avoid with nitrates and riociguat.
• Macitentan 10 mg once daily, or ambrisentan 5 to 10 mg once daily (liver tests monthly for bosentan and ambrisentan as directed; exclude pregnancy monthly); bosentan 62.5 mg twice daily for 4 weeks then 125 mg twice daily (monthly liver tests).
• Selexipag 200 microgram orally twice daily, increased by 200 microgram twice daily weekly to a maximum of 1600 microgram twice daily.
• Parenteral prostacyclin (epoprostenol or treprostinil) for high risk disease.
• Sotatercept 0.3 mg/kg subcutaneously, then 0.7 mg/kg every 3 weeks, added to background therapy; monitor haemoglobin and platelets.

Chronic thromboembolic pulmonary hypertension. Lifelong anticoagulation (warfarin to an INR of 2.0 to 3.0, or apixaban 5 mg twice daily). Pulmonary endarterectomy for operable disease. Balloon pulmonary angioplasty or riociguat 1 mg three times daily increased every 2 weeks to a maximum of 2.5 mg three times daily (no combination with phosphodiesterase-5 inhibitors or nitrates) for inoperable disease. Monitor blood pressure and exclude pregnancy.

Lung disease and hypoxaemia. Long term oxygen therapy for at least 15 hours daily when PaO2 is 7.3 kPa (55 mmHg) or under, or under 8.0 kPa (60 mmHg) with cor pulmonale or polycythaemia. Pulmonary arterial hypertension drugs are not used in COPD-related pulmonary hypertension. Inhaled treprostinil in pulmonary hypertension with interstitial lung disease starts at 3 breaths (18 microgram) four times daily, increased by 3 breaths each 1 to 2 weeks to a target of 9 to 12 breaths four times daily.

Rhythm and other measures.

• Atrial arrhythmia is poorly tolerated; restore sinus rhythm by cardioversion or amiodarone 200 mg daily after loading (thyroid and liver tests every 6 months). Anticoagulate by risk (apixaban 5 mg twice daily, 2.5 mg if two of age 80 or over, weight 60 kg or under, creatinine 133 micromol/L or over).
• Iron deficiency: correct with intravenous iron (ferric derisomaltose 20 mg/kg, maximum 1000 mg).
• Vaccination against influenza, pneumococcus and COVID-19, supervised exercise rehabilitation, and avoidance of altitude and pregnancy in pulmonary hypertension.
• Tricuspid valve repair or transcatheter intervention for severe tricuspid regurgitation with right ventricular dilatation, ideally before irreversible dysfunction.
• Beta blockers, ACE inhibitors and ARBs have no role in isolated pulmonary arterial hypertension and may harm.
• Advanced disease: atrial septostomy, Potts shunt in selected cases, and lung or heart lung transplantation.

Monitoring. Clinical review every 3 to 6 months, weight and symptoms at each visit, NT-proBNP and six minute walk every 3 to 6 months, echocardiography every 6 to 12 months. Check creatinine, electrolytes and liver tests with every diuretic change and at least every 3 months. Perform right heart catheterisation with clinical change or treatment escalation.

Referral and escalation. Refer all suspected pulmonary hypertension and unexplained right heart failure to a pulmonary hypertension centre. Urgent referral for exertional syncope or presyncope, haemoptysis, refractory ascites, rising bilirubin or creatinine, a low output state (cold peripheries, narrow pulse pressure), resting hypoxaemia, deterioration after infection or arrhythmia, intermediate or high risk status, or need for intravenous therapy.

Special groups.

• Pregnancy: high maternal mortality in pulmonary arterial hypertension and Eisenmenger syndrome, so pregnancy is advised against; endothelin receptor antagonists, riociguat and sotatercept are teratogenic and require reliable contraception.
• Older adults: use lower diuretic starting doses, watch for hyponatraemia and falls.
• Kidney or liver impairment: reduce or avoid ambrisentan, bosentan and macitentan in significant hepatic impairment; adjust sildenafil and spironolactone by eGFR; monitor potassium closely.
• Region specific: schistosomiasis associated pulmonary hypertension and rheumatic mitral and tricuspid disease are frequent causes and need specific treatment alongside pulmonary vasodilator therapy.