As a cardiologist, one encounters a myriad of questions from patients regarding the complexities of heart failure. Among the inquiries that arise frequently is the classification of right heart failure as either diastolic or systolic. Given the significance of this distinction in guiding treatment strategies and prognostication, it is imperative to delve into the intricacies of right heart failure and elucidate whether it aligns more closely with the diastolic or systolic paradigm.
What Is Right Heart Failure？
The right side of the heart is responsible for receiving deoxygenated blood returning from the body and pumping it to the lungs for oxygenation. Right heart failure occurs when the right ventricle fails to effectively perform this function, leading to impaired cardiac output and venous congestion. Common etiologies of right heart failure include ：
- pulmonary hypertension
- chronic lung disease
- left heart failure
- valvular heart disease
What Is Definitions And Concepts of Diastolic Versus Systolic Dysfunction?
Diastolic dysfunction refers to impaired relaxation or compliance of the ventricle during diastole, leading to elevated filling pressures and preserved ejection fraction.
In contrast, systolic dysfunction involves impaired contractility of the ventricle during systole, resulting in reduced ejection fraction and diminished cardiac output. However, applying these concepts to right heart failure warrants careful consideration due to inherent differences in anatomy, physiology, and hemodynamics.
Is Right Heart Failure Diastolic?
Acute right heart failure refers to a clinical syndrome in which the contractility of the right ventricular myocardium sharply decreases or the preload and postload of the right ventricle suddenly increase due to certain reasons, resulting in a sharp decrease in right ventricular blood output.
Acute heart failure can start suddenly or worsen acutely on the basis of original chronic heart failure. Most of the symptoms are systolic heart failure or diastolic heart failure. Most patients have organic cardiovascular diseases before the onset.
Pathophysiology of Right Heart Failure
In right heart failure, the primary pathophysiological derangement involves an increase in right ventricular afterload, typically secondary to pulmonary hypertension. Chronic elevation in pulmonary vascular resistance leads to right ventricular hypertrophy and ultimately, right ventricular failure. The resulting increase in right atrial pressure leads to systemic venous congestion, manifested clinically as peripheral edema, ascites, and hepatic congestion.
Clinical Manifestations of Right Heart Failure
The clinical manifestations of right heart failure are predominantly related to venous congestion and impaired cardiac output. Common symptoms include:
- Peripheral edema, particularly in the lower extremities.
- Ascites and abdominal distension due to hepatic congestion and fluid retention.
- Hepatomegaly and elevated jugular venous pressure on physical examination.
- Fatigue, dyspnea, and exercise intolerance due to decreased cardiac output and tissue perfusion.
- Peripheral cyanosis and cool extremities in advanced cases.
Diagnostic Evaluation of Right Heart Failure
The diagnosis of right heart failure is established through a combination of clinical assessment, imaging studies, and laboratory tests. Key investigations include:
Echocardiography to assess right ventricular size and function, pulmonary artery pressures, and the presence of valvular or structural abnormalities.
Right heart catheterization to directly measure pulmonary artery pressures, right atrial pressure, and cardiac output, providing definitive hemodynamic data.
Blood tests to evaluate for markers of cardiac injury, renal function, and electrolyte abnormalities.
Treatment of Right Heart Failure
The management of right heart failure hinges on addressing the underlying etiology, optimizing volume status, and alleviating symptoms of congestion. While there is no specific medication approved solely for the treatment of right heart failure, pharmacotherapy aimed at reducing pulmonary vascular resistance and improving right ventricular function can play a crucial role in symptom management and disease modification.
Best Medication for Congestive Heart Failure
Diuretics: Diuretics are cornerstone therapy for managing volume overload and relieving symptoms of congestion in right heart failure. Loop diuretics, such as furosemide and bumetanide, are typically preferred due to their potent diuretic effects and ability to mobilize fluid from the extravascular space.
Vasodilators: Pulmonary vasodilators, including phosphodiesterase-5 (PDE-5) inhibitors (e.g., sildenafil) and endothelin receptor antagonists (e.g., bosentan), can reduce pulmonary vascular resistance and improve right ventricular function in select patients with pulmonary hypertension.
Inotropes: Inotropes such as dobutamine and milrinone may be considered in cases of acute decompensated right heart failure or refractory symptoms despite optimal medical therapy. However, their use is associated with significant risks and should be reserved for carefully selected patients under close hemodynamic monitoring.
Anticoagulants: Given the increased risk of thromboembolic events in patients with right heart failure and associated conditions such as atrial fibrillation and pulmonary embolism, anticoagulation with agents like warfarin or direct oral anticoagulants (DOACs) may be indicated to prevent thromboembolic complications.
Beta-Blockers: While traditionally contraindicated in right heart failure due to concerns about exacerbating pulmonary hypertension and worsening right ventricular function, emerging evidence suggests that selective beta-blockers such as carvedilol may have beneficial effects in certain patients with pulmonary hypertension and right heart failure.
Conclusion
right heart failure represents a complex and multifaceted condition characterized by impaired right ventricular function and venous congestion. While the concepts of diastolic and systolic dysfunction are well-established in left heart failure, applying these paradigms to right heart failure is challenging due to differences in anatomy, physiology, and hemodynamics. Instead, right heart failure is best understood as a unique entity characterized by increased afterload, pulmonary vascular remodeling, and venous congestion. Treatment strategies focus on addressing the underlying etiology, optimizing volume status, and alleviating symptoms through a combination of pharmacotherapy, lifestyle modifications, and, in some cases, advanced interventions such as cardiac transplantation or mechanical circulatory support.
FAQs
Heart Failure Grade:
Heart failure is often graded based on the severity of symptoms and the degree of functional limitation. One commonly used classification system is the New York Heart Association (NYHA) functional classification:
Class I (Mild): Patients with heart disease but without resulting limitations of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea (shortness of breath), or anginal pain.
Class II (Mild to Moderate): Patients with heart disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or anginal pain.
Class III (Moderate to Severe): Patients with heart disease resulting in marked limitation of physical activity. They are comfortable at rest, but less than ordinary activity causes fatigue, palpitation, dyspnea, or anginal pain.
Class IV (Severe): Patients with heart disease resulting in an inability to carry on any physical activity without discomfort. Symptoms of heart failure are present even at rest, and any physical activity worsens them.
End-of-Life Signs in Heart Failure Patients:
These signs may include:
- Severe dyspnea or shortness of breath, even at rest.
- Profound fatigue and weakness.
- Recurrent hospitalizations despite optimal medical therapy.
- Inability to perform activities of daily living.
- Significant weight loss or cachexia.
- Refractory fluid retention leading to severe peripheral edema, ascites, or pleural effusions.
- Marked decline in renal function.
- Changes in mental status or cognitive decline.
- Cardiogenic shock or refractory arrhythmias.
Duration of Right Heart Failure Cure:
The duration for right heart failure to be “cured” varies greatly depending on the underlying cause, the severity of the condition, and the effectiveness of treatment. In many cases, right heart failure is managed rather than cured, focusing on alleviating symptoms, improving quality of life, and prolonging survival through pharmacotherapy, lifestyle modifications, and sometimes surgical interventions or device therapy. The goal of treatment is to optimize right ventricular function, reduce pulmonary vascular resistance, and alleviate venous congestion. With appropriate management, some patients may experience significant improvement in symptoms and functional status, but complete resolution of right heart failure may not always be achievable.
Prevalence of Right Heart Failure:
Right heart failure is less common than left heart failure but can occur in various clinical scenarios, including pulmonary hypertension, chronic lung disease, left heart failure, and valvular heart disease. For example, pulmonary arterial hypertension (PAH), a condition characterized by elevated pulmonary vascular resistance, can lead to right heart failure if left untreated. PAH affects an estimated 15 to 50 individuals per million adults worldwide. Chronic obstructive pulmonary disease (COPD) and other forms of chronic lung disease are also common causes of right heart failure, particularly in older adults with a history of smoking. Overall, while right heart failure may not be as prevalent as left heart failure, it remains a significant clinical entity with substantial morbidity and mortality.