What is Right Heart Failure?
When we talk about heart failure, we often focus on the left ventricle, or the left side of the heart, and tend to ignore the right side. However, the right ventricle is unique in both its structure and function, and can be affected by various diseases just like the left side. This piece examines the normal structure and how the right ventricle works under normal circumstances. It also discusses what happens when the right ventricle fails to function properly and provides details on medical and surgical treatments for the different conditions that may lead to this failure.
What Causes Right Heart Failure?
Right ventricular failure (RVF), which is essentially a state where the right chamber of your heart is unable to function properly, often happens because the left chamber (ventricular) of the heart is also failing, and this puts too much stress on the right side. This can be a result of either an increase in blood pressure or excess blood volume.
Some temporary (or transient) conditions causing this heart chamber failure are pneumonia, pulmonary embolism – a blood clot in lungs, being on a mechanical ventilator, or experiencing acute respiratory distress syndrome, which is a severe lung condition causing shortness of breath.
Long-term (or chronic) conditions also cause this rise in blood pressure leading to RVF. These include primary and secondary pulmonary hypertension – high blood pressure in the arteries of the lungs – which can be caused by chronic obstructive pulmonary disease or scarred lungs due to fibrosis. Being born with certain heart defects can also lead to this type of heart failure.
Volume overload, meaning that the heart is handling too much blood, is another cause of RVF. This occurs in cases of heart valve insufficiencies, or when you’re born with certain heart defects causing an abnormal flow of blood.
RVF can also be caused by diseases affecting the right chamber of the heart, such as ischemia or infarct – reduced blood-flow leading to damage, conditions that cause deposits in the heart like amyloidosis or sarcoidosis, arrhythmogenic right ventricular dysplasia – a rare type of cardiomyopathy, or other general heart muscle diseases. Small-vessel diseases can also lead to RVF.
Finally, another cause of RVF includes impaired filling of the heart, when the heart can’t fill with blood properly. This can happen due to tightness surrounding the heart, a faulty heart valve, conditions causing low blood pressure like systemic vasodilation shock, conditions causing fluid around the heart like a cardiac tamponade, superior vena cava syndrome leading to blocked blood flow to the heart, or simply because of low blood volume throughout the body.
Risk Factors and Frequency for Right Heart Failure
Right ventricular failure (RVF) is often a consequence of left ventricular failure (LVF). Patients with this combined condition, known as biventricular failure, unfortunately face a lower survival rate. Specifically, their 2-year survival stands at 23% compared to 71% for patients with just LVF.
Some studies provide more insights about RVF. For instance, in the CHARITEM registry, RVF comprised 2.2% of heart failure hospital admissions, with over one fifth resulting from LVF. In the Egyptian Heart Failure-LT registry, RVF was seen in 4.5% of patients with rapidly worsening heart failure compared to 3% in other regions surveyed by the European Society of Cardiology. This higher prevalence in Egypt may be attributed to the increased incidence of rheumatic heart disease in the region.
Signs and Symptoms of Right Heart Failure
Right ventricular failure (RVF) is a medical condition that requires careful evaluation to identify how serious it is, what caused it, and what the best treatment might be. This evaluation starts with a detailed medical history and physical examination.
Patients with RVF often show issues with oxygen supply (hypoxemia) and blood flow (systemic venous congestion). Symptoms could include:
- Shortness of breath
- Chest discomfort
- Heart palpitations
- Swelling in body parts
The doctor might also find the following during a physical examination:
- Swelling in the neck veins (Jugular venous distension)
- Increased blood flow in the liver when pressure is applied over the jugular vein (Hepatojugular reflux)
- Swelling of the legs, ankles and feet (Peripheral edema)
- Enlarged liver or spleen (Hepatosplenomegaly) or a pulsating liver (hepatic pulsation)
- Fluid buildup in the abdomen (Ascites)
- Total body swelling (Anasarca)
- A distinct heart sound known as S3 gallop
- An audible murmur caused by backward flow of blood from the right ventricle into the right atrium (TR murmur)
- A visible or palpable lifting of the chest wall (RV heave)
- Signs of left ventricular failure (LVF)
- A pulse that varies with respiration (Paradoxical pulse)
In severe cases, when the right ventricle is unable to maintain the output of blood, the patient may experience presyncope (feeling faint) or syncope (fainting) along with:
- Low blood pressure (Hypotension)
- Rapid heart rate (Tachycardia)
- Cool skin on arms and legs
- Slow return of skin color to normal after being pressed (Delayed capillary refill)
- Decrease in brain function (Central nervous system depression)
- Reduced urine production (Oliguria)
Testing for Right Heart Failure
After completing your medical history and physical exam, your doctor might continue with the assessment of your heart function. This could involve an electrocardiogram, which records the electrical signals in your heart, a blood gas test, which measures the levels of oxygen and carbon dioxide in your blood, a blood lactate test, which measures the amount of lactate in your blood, and a chest X-ray. They may also check the function of your kidneys and liver to understand the severity of your condition, and might also conduct a D-Dimer test if a pulmonary embolism (a blood clot in the lungs) is suspected.
There aren’t any biomarkers that are specific for right ventricular failure (RVF), but B-type natriuretic peptide and cardiac troponin are highly sensitive tests that could identify early signs of RVF and heart muscle injury. If the levels of these biomarkers are elevated, it could mean that the prognosis of RVF due to pulmonary arterial hypertension (PAH) is poor.
Non-invasive tests are a crucial part of the evaluation process. Echocardiography, which uses sound waves to create a detailed image of your heart, is commonly used to observe the size, blood flow, and function of the right ventricle of your heart. This process involves taking images from different angles to measure various aspects, such as the size of the right ventricle and atrium and the movement of the tricuspid annulus, which gives an estimate of the right ventricular function. It also measures right ventricular strain and other indices related to the functioning of your heart.
Nuclear angiography, a radioactive imaging technique, was previously the gold standard for measuring the efficiency of pumping of the right ventricle, but this technique has its limitations.
Today, Magnetic Resonance Imaging (MRI) is regarded as the gold standard for measuring right ventricular volumes and function. The use of MRI is limited due to its prohibitive cost, the long duration of data acquisition and analysis, and because it cannot be used in individuals with implantable cardiac devices.
Computed tomography (CT) can be used to measure right ventricular efficiency and volumes. However, this requires extra radiation exposure and hence is not regularly used.
Lastly, right heart catheterization is an invasive but safe and valuable procedure done to diagnose and treat RVF. It involves inserting a thin tube into the right side of your heart to measure its pressures directly. The results from this procedure have significant predictive value for more adverse outcomes in PAH.
Treatment Options for Right Heart Failure
When a person has acute right ventricular failure (RVF), which means their heart is having trouble pumping blood, doctors will initially assess the severity of their condition and decide whether intensive or intermediate care is needed. The team will also quickly start addressing any factors that might have triggered the condition, such as an infection, abnormal heart rhythms, or drug withdrawal. If the RVF was caused by a heart attack in the right ventricle or a high-risk blood clot in the lungs, urgent treatment will be necessary.
The main areas of focus in treating acute RVF are balancing the patient’s fluid levels, increasing the heart’s pumping power, and reducing the pressure the heart has to pump against.
In some cases, adding more volume through fluids may help if the patient has low blood pressure and filling pressures. However, too much fluid can overwork the heart and lead to a decrease in the heart’s output.
It’s also important to manage any abnormal heart rhythms and treat any rapid or slow heart rates that could be harming the heart’s output. Certain medications, such as digoxin, might be useful in these cases but need to be used carefully due to their potential side effects.
The team may also use drugs that help the heart pump more effectively or reduce the pressure the heart works against. Some of these drugs have also been found to increase the heart’s contraction strength.
For patients who are on a breathing machine, the care team needs to carefully manage the settings as high pressure and volume can increase strain on the heart.
If the patient’s RVF does not improve with medical treatments, surgical interventions may be necessary. In severe cases, patients may need artificial heart devices or a heart or lung transplant as a temporary solution or as a bridge to possible transplantation. Other surgeries or procedures might be required based on the patient’s specific conditions.
Certain factors can make a patient ineligible for surgical interventions, such as irreversible damage to other organs due to the RVF.
Despite the severity of acute RVF, there are a variety of treatment options available that can greatly improve a patient’s condition, and potentially even save their life. This underscores the importance of early detection and prompt treatment.
What else can Right Heart Failure be?
- Liver disease (Cirrhosis)
- Pneumonia acquired outside of a hospital setting (Community-Acquired Pneumonia)
- Lung damage which causes shortness of breath (Emphysema)
- An autoimmune disease that affects the lungs and kidneys (Goodpasture Syndrome)
- Scarring of the lungs with unknown cause (Idiopathic Pulmonary Fibrosis)
- Scarring of the lungs with a known cause (Non-idiopathic Pulmonary Fibrosis)
- Heart attack (Myocardial Infarction)
- Health condition that leads to damage and inflammation in the kidneys (Nephrotic Syndrome)
- Build-up of fluid in the lungs usually due to severe brain injury (Neurogenic Pulmonary Edema)
- X-ray images showing an abnormal collection of air or gas in the space between the lung and chest wall (Pneumothorax Imaging)
- A blood clot lodged in the lung’s vessels (Pulmonary Embolism)
- Lung failure to perform its primary function (Respiratory Failure)
- Condition when the veins have problems sending blood from the legs back to the heart (Venous Insufficiency)
- Pneumonia caused by a virus (Viral Pneumonia)
