What are the causes and treatments of right heart failure?

Right Heart Failure: Causes and Treatment

Causes of Right Heart Failure

Right heart failure results from the inability of the right ventricle to support optimal circulation, most commonly caused by pulmonary hypertension, left heart disease, right ventricular infarction, pulmonary embolism, chronic lung disease, and valvular abnormalities. 1, 2, 3

Primary Etiologies

• Pulmonary hypertension is the principal cause of chronic right heart failure and the leading cause of death in patients with pulmonary arterial hypertension 1
• Left heart disease including coronary artery disease, hypertension, valvular heart disease, cardiomyopathies, and myocarditis can all lead to right heart failure 4
• Acute right ventricular infarction typically related to acute RV ischemia in acute coronary syndromes, particularly involving the right coronary artery 1
• Massive pulmonary embolism causing acute elevation in pulmonary vascular resistance 1, 2
• Chronic lung conditions including COPD and interstitial lung disease leading to cor pulmonale 2, 3
• Valvular disease including acute mitral or aortic valve incompetence, endocarditis, prosthetic valve thrombosis, and tricuspid regurgitation 1
• Congenital heart disease with chronic volume or pressure overload 3
• Postcardiotomy shock following cardiac surgery 1

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Treatment Approach

Initial Assessment and Stabilization

Immediately identify the underlying etiology as management differs dramatically based on cause—progressive isolated RV failure should be suspected to be caused by pulmonary hypertension, while acute presentations may indicate RV infarction or pulmonary embolism. 5

• Continuously monitor heart rate, rhythm, blood pressure, and oxygen saturation for at least the first 24 hours 5
• Maintain oxygen saturation above 90% at all times 5, 6
• Consider pulmonary artery catheterization in patients who are refractory to pharmacological treatment, persistently hypotensive, or have uncertain left ventricular filling pressure 5

Cause-Specific Management

For RV Infarction

• Perform urgent coronary angiography and revascularization immediately for acute coronary syndrome with RV involvement 5
• Administer volume loading with normal saline (500-ml bolus, followed by 500 ml/h) unless there are signs of left heart volume overload 5
• Early revascularization of the right coronary artery and its ventricular branches is recommended 1

For Pulmonary Hypertension-Related RHF

• Pulmonary vasodilators are the cornerstone of treatment including type V phosphodiesterase inhibitors, endothelin antagonists, and prostacyclin analogues 5
• Consider sildenafil 20 mg three times daily for right heart failure associated with pulmonary hypertension 5
• Inhaled nitric oxide (5-40 ppm) may be considered for acute management 5

For Valvular Disease

• Perform transoesophageal echocardiography to rule out structural defects 1
• Surgical consultation is warranted early, particularly for severe acute aortic or mitral regurgitation 1
• For prosthetic valve thrombosis: thrombolysis is used for right-sided prosthetic valves and high-risk surgical candidates; surgery is preferred for left-sided prosthetic valve thrombosis 1

Pharmacological Management

Diuretics

Loop diuretics (e.g., furosemide) are essential for symptomatic treatment when fluid overload is present with pulmonary congestion or peripheral edema, but must be used cautiously in isolated RV failure to avoid compromising RV filling pressure. 5, 6

• Start with standard doses and progressively increase if response is insufficient 6
• Consider doubling the dose up to furosemide 500 mg equivalent if no initial response 5
• For persistent fluid retention, combine loop diuretics with thiazides 6
• In severe chronic heart failure, add metolazone with frequent monitoring of creatinine and electrolytes 6
• Critical caveat: Diuretics and vasodilators should be used cautiously or avoided in isolated RV failure to prevent reducing RV filling pressure 5
• Avoid excessive fluid administration in patients with a massively dilated right ventricle as this may increase right ventricular distention and compromise left ventricular filling 5

ACE Inhibitors

• ACE inhibitors are recommended as first-line therapy in patients with reduced left ventricular systolic function who also have right heart failure 5
• Start with a low dose and build up to recommended maintenance dosages shown to be effective in large trials 1, 6
• Avoid excessive diuresis before treatment; reduce or withhold diuretics for 24 hours before initiating 1, 6
• Avoid potassium-sparing diuretics during initiation of therapy 1, 6
• Monitor blood pressure, renal function, and electrolytes 1-2 weeks after each dose increment, at 3 months, and subsequently at 6-month intervals 1, 6

Inotropic Support

• Dobutamine at 2.5-5.0 μg/kg/min can improve right ventricular output 5
• Consider milrinone (0.25-0.75 μg/kg/min) as an alternative inotrope, particularly for its additional pulmonary vasodilatory effects, but monitor for hypotension 5
• Inotropic agents may be deleterious in pulmonary edema without careful hemodynamic assessment 1

Mechanical Circulatory Support

• Consider intra-aortic balloon pump or other mechanical circulatory support in patients without contraindications 5
• Mechanical support is increasingly used to facilitate recovery or as a bridge to transplant 7

Medications to Avoid

Certain medications should be avoided or used with extreme caution in right heart failure: 5

• NSAIDs and COX-2 inhibitors (worsen fluid retention and reduce diuretic effectiveness) 5, 6
• Class I antiarrhythmic agents 5
• Calcium antagonists (particularly diltiazem or verapamil in patients with reduced ejection fraction) 5, 6
• Tricyclic antidepressants 5
• Corticosteroids 5
• Avoid combination of ACE inhibitors, ARBs, and mineralocorticoid receptor antagonists due to increased risk of renal dysfunction and hyperkalemia 6

Non-Pharmacological Management

• Control sodium intake, particularly in patients with severe heart failure 1, 8
• Avoid excessive fluids only in severe heart failure 1, 8
• Avoid excessive alcohol intake 1, 8
• Daily physical and leisure activities in stable patients to prevent muscle deconditioning 1, 8
• Exercise training programs are recommended for stable NYHA class II-III patients 1, 8

Discharge Planning

Before discharge, ensure the acute episode has resolved completely, congestion is absent, a stable oral diuretic regimen has been established for at least 48 hours, long-term disease-modifying therapy is optimized, and appropriate patient and family education has been provided. 5, 8

• Monitor renal function, electrolytes, potassium, and sodium daily during IV therapy and when adjusting renin-angiotensin-aldosterone system antagonists 5

Key Clinical Pitfalls

• Do not treat isolated RV failure the same as left heart failure—aggressive diuresis can be catastrophic by reducing RV preload 5
• Recognize that RV failure patients are preload-dependent—they may require fluid resuscitation rather than diuresis in certain contexts 2
• Avoid intubation if possible as positive pressure ventilation can worsen RV afterload and hemodynamics 2
• Address hypotension rapidly with vasopressors rather than aggressive fluid boluses in the setting of massive RV dilation 5, 2