Entresto: A New Hope for Improving Heart Ejection Fraction

Understanding Entresto and Its Impact on Heart Ejection Fraction

Heart failure is a serious medical condition affecting millions worldwide, and in India, its prevalence is a growing concern. It signifies a state where the heart struggles to pump blood effectively to meet the body's needs for oxygen and nutrients. A key indicator of heart function is the ejection fraction (EF), which measures the percentage of blood pumped out of the heart's main pumping chamber (the left ventricle) with each beat. A normal EF typically ranges from 50% to 70%. When this percentage drops below 40%, it can signal heart failure or cardiomyopathy, a condition where the heart muscle is weakened or damaged.

Fortunately, medical advancements have introduced new treatment options. One such medication that has shown significant promise is Entresto. Initially approved for heart failure with reduced ejection fraction (HFrEF), also known as systolic heart failure, Entresto has now also been cleared by regulatory bodies for treating heart failure with preserved ejection fraction (HFpEF). This article delves into how Entresto works, its potential benefits, side effects, and what Indian patients need to know about this innovative treatment.

What is Ejection Fraction and Why Does it Matter?

Ejection fraction is a crucial metric used by doctors to assess how well your heart is pumping. Imagine your heart's left ventricle as a pump. With each contraction (heartbeat), it pushes a certain amount of blood out into the body. The ejection fraction is the percentage of blood that is expelled from the ventricle during this contraction. A higher EF indicates a stronger, more efficient heart pump. Conversely, a lower EF suggests that the heart muscle is not contracting as forcefully as it should, leading to reduced blood flow and potential symptoms of heart failure.

Conditions that can lead to a reduced ejection fraction include:

• Coronary artery disease (blockages in heart arteries)
• Heart attack (myocardial infarction)
• High blood pressure (hypertension) that is poorly controlled
• Heart valve problems
• Cardiomyopathy (diseases of the heart muscle)
• Congenital heart defects (heart problems present from birth)

How Does Entresto Work?

Entresto is not a single drug but a combination of two medications working together synergistically. It belongs to a class of drugs called angiotensin receptor-neprilysin inhibitors (ARNIs). The two components are:

• Sacubitril: This is a neprilysin inhibitor. Neprilysin is an enzyme that breaks down certain naturally occurring substances in the body that help dilate blood vessels and reduce the workload on the heart. By inhibiting neprilysin, sacubitril allows these beneficial substances to remain active for longer, leading to widened blood vessels and reduced blood pressure.
• Valsartan: This is an angiotensin receptor blocker (ARB). It works by blocking the action of angiotensin II, a hormone that causes blood vessels to constrict (narrow) and raises blood pressure. By blocking angiotensin II, valsartan helps to relax blood vessels, lower blood pressure, and reduce the strain on the heart. It can also help protect the kidneys, which are often affected by heart failure.

The combination of sacubitril and valsartan in Entresto offers a dual benefit: it not only helps to relax and widen blood vessels but also enhances the body's natural mechanisms that support heart health. This approach is often more effective than using either an ACE inhibitor or an ARB alone.

Entresto and Ejection Fraction Improvement

Clinical studies, such as the landmark PROVE-HF trial, have demonstrated Entresto's effectiveness in improving ejection fraction. In this trial, patients treated with Entresto showed a significant increase in their left ventricular ejection fraction over time. For instance, a median increase from 28.2% to 37.8% was observed at 12 months, with a notable 5.2% increase seen within the first 6 months. This improvement suggests that Entresto can help the heart muscle regain some of its pumping strength, leading to better blood circulation and potentially alleviating symptoms of heart failure.

Entresto is prescribed to improve the heart's ejection fraction and reduce the risk of hospitalizations in individuals with symptomatic heart failure.

Who Can Benefit from Entresto?

Entresto is approved for treating symptomatic heart failure in adults and children aged one year and older. It is particularly beneficial for individuals with:

• Heart failure with reduced ejection fraction (HFrEF): Where the heart's pumping ability is significantly impaired.
• Heart failure with preserved ejection fraction (HFpEF): Where the heart muscle is stiff and cannot relax properly to fill with blood, even though the pumping strength might appear normal.

Your doctor will assess your specific condition, medical history, and other medications before deciding if Entresto is the right choice for you.

Potential Side Effects of Entresto

Like all medications, Entresto can cause side effects. While many people tolerate it well, it's important to be aware of potential risks. Common side effects may include:

• Dizziness or lightheadedness
• Fatigue
• Cough
• High potassium levels (hyperkalemia)
• Kidney problems, including kidney failure
• Low blood pressure (hypotension)

Important Warning for Pregnant Women: Entresto carries a boxed warning from the FDA regarding its use during pregnancy. It can cause serious harm or death to a developing fetus, particularly affecting the baby's kidneys. Women who are pregnant or planning to become pregnant should not take Entresto.

If you experience any severe or persistent side effects, it is crucial to contact your doctor immediately.

Factors to Consider Before Taking Entresto

Your doctor might advise against Entresto if you have:

• A history of angioedema (severe swelling under the skin)
• Hypersensitivity to sacubitril, valsartan, or any component of Entresto
• Certain kidney conditions
• If you are taking specific other medications, such as Tekturna (aliskiren) if you have diabetes.

It is vital to inform your doctor about all your medical conditions and all the medications you are currently taking, including over-the-counter drugs and herbal supplements.

How Long Does it Take for Entresto to Work?

Entresto is typically taken twice a day. It usually takes about 3 days of consistent dosing to reach steady levels in your body. The medication starts to be absorbed within 30 minutes to 2 hours after taking a dose. While some improvements may be noticed relatively quickly, the full benefits, including significant improvements in ejection fraction, can take several months of regular use.

Entresto and Life Expectancy

While Entresto is not a cure for heart failure, studies have shown that it can significantly improve the quality of life for patients. By improving heart function and reducing the workload on the heart, Entresto has been shown to reduce the need for hospitalizations related to heart failure. This reduction in hospital stays contributes to better overall health and potentially a longer, more fulfilling life for individuals managing this chronic condition.

When to Consult a Doctor

It is essential to consult your doctor if you experience any symptoms of heart failure, such as:

• Shortness of breath, especially during activity or when lying down
• Fatigue and weakness
• Swelling in your legs, ankles, and feet (edema)
• Rapid or irregular heartbeat
• Persistent cough or wheezing
• Sudden weight gain

If you have been diagnosed with heart failure, discuss with your cardiologist whether Entresto is a suitable treatment option for you. Regular follow-up appointments are crucial to monitor your response to the medication and manage any potential side effects.

Frequently Asked Questions (FAQ)

Q1: Can Entresto be taken with other heart medications?

A: Yes, Entresto is often prescribed in conjunction with other heart failure medications. However, it's crucial to inform your doctor about all the medications you are taking, as some combinations may not be advisable.

Q2: Does Entresto have any long-term side effects?

A: Long-term side effects can include chronic kidney issues or electrolyte imbalances. Regular monitoring by your doctor is essential to detect and manage any long-term effects.

Q3: Is Entresto available in India?

A: Yes, Entresto is available in India and is prescribed by cardiologists for the management of heart failure.

Q4: How does Entresto compare to ACE inhibitors or ARBs?

A: Entresto is a combination of a neprilysin inhibitor (sacubitril) and an ARB (valsartan). It is often found to be more effective than ACE inhibitors or ARBs alone in improving ejection fraction and reducing hospitalizations for heart failure.

Q5: What is the dosage of Entresto?

A: The dosage is determined by your doctor based on your condition and previous medications. It is typically taken twice daily. Starting doses are usually lower and gradually increased.