Heart Failure

Heart failure is a serious medical condition that affects millions of people worldwide. It occurs when the heart muscle is unable to pump enough blood to meet the body's demands for oxygen and nutrients. This can lead to a range of symptoms that can significantly impact a person's quality of life. In this article, we will discuss the causes, stages, and types of heart failure that are crucial for effective management and prevention.

What is Heart Failure?

Heart failure, also known as congestive heart failure (CHF), is a condition in which the heart muscle becomes weakened or damaged, making it difficult for the heart to pump blood efficiently (Heidenreich et al., 2022). This can cause blood to back up in the lungs, leading to shortness of breath, and can also cause fluid retention in the legs, ankles, and feet. Heart failure is a progressive condition that can worsen over time if not properly managed, but with early diagnosis and appropriate treatment, many people with heart failure can lead full and active lives.

Heart failure is commonly classified by how well the left ventricle pumps blood (ejection fraction) and by which side of the heart is predominantly affected. The main functional types are heart failure with reduced ejection fraction (HFrEF), heart failure with mildly reduced ejection fraction (HFmrEF), and heart failure with preserved ejection fraction (HFpEF), and anatomically as left‑sided, right‑sided, or biventricular heart failure. Left‑sided and right‑sided heart failure describe which chambers are most affected and often coexist in advanced disease.

• Left-sided heart failure: This type of heart failure occurs when the left ventricle, which is responsible for pumping oxygenated blood to the body, is not functioning properly. There are two subtypes of left-sided heart failure:
• Systolic: In this subtype, the left ventricle cannot contract efficiently, leading to reduced blood ejection.
• Diastolic: In this subtype, the left ventricle cannot relax normally, making it difficult for the heart to fill with blood.

Right-sided heart failure: This type of heart failure occurs when the right ventricle, which is responsible for pumping deoxygenated blood to the lungs, is not functioning properly. Right-sided heart failure often develops as a result of left-sided heart failure, as the increased pressure in the lungs can put strain on the right side of the heart.

The early signs of heart failure include:

• Tiredness

• Shortness of breath

• Cough or wheezing

• Swelling (oedema)

• Trouble doing daily activities

Heart failure can manifest through various symptoms, depending on the severity and progression of the condition. Some common symptoms include:

• Shortness of breath: Individuals may experience breathlessness during physical activity or while resting, and they might be awakened from sleep due to difficulty breathing.

• Fatigue and weakness: Many patients report feeling tired and weak, particularly in the legs, which can make daily activities challenging.

• Persistent coughing or wheezing: A persistent cough may occur, often accompanied by pink or blood-tinged mucus due to fluid buildup in the lungs.

• Buildup of excess fluid: Patients may notice swelling in the feet, ankles, legs, fingers, and abdomen, which can lead to unexpected weight gain.

• Lack of appetite and nausea: Some individuals may feel full or experience nausea due to digestive issues caused by reduced blood flow to the stomach.

• Confusion and impaired thinking: Reduced blood flow to the brain can result in symptoms such as memory loss and disorientation.

• Increased heart rate: Patients may experience heart palpitations, feeling as though their heart is racing or throbbing as it tries to compensate for decreased pumping capacity.

• Weight changes: Sudden weight gain or loss can indicate fluid retention or issues with nutrient absorption, both of which are common in heart failure.

If you notice any of these heart failure symptoms, especially if they are new, worsening, or frequent, it's essential to seek medical attention promptly for an accurate diagnosis.

The stages of heart failure include:

• Stage A (at risk for heart failure): Individuals with risk factors such as diabetes, hypertension, or a family history of heart failure but without structural heart disease or symptoms of heart failure.
• Stage B (pre-heart failure): Patients with structural heart disease but no symptoms of heart failure. This includes those with structural heart disease (such as left ventricular dysfunction or hypertrophy) or persistently elevated cardiac biomarkers, but without signs or symptoms of heart failure.
• Stage C (symptomatic heart failure): Individuals with structural heart disease and current or previous symptoms of heart failure. This stage is characterised by the presence of symptoms that significantly impact daily life (Heidenreich et al., 2022; Shams et al., 2025).
• Stage D (advanced heart failure): Patients with refractory, severe symptoms or recurrent hospitalisations despite optimal guideline-directed medical therapy (GDMT), often requiring specialised advanced heart failure interventions (such as continuous inotropes, mechanical circulatory support, or transplant evaluation). This stage indicates advanced disease requiring specialised interventions.

Heart failure can develop due to various underlying conditions that damage or weaken the heart muscle. Some of the main causes of heart failure include:

• Coronary artery disease (CAD): This condition involves the narrowing or blockage of the arteries that supply blood and oxygen to the heart. Over time, this can weaken the heart muscle, leading to heart failure.

• High blood pressure: Uncontrolled high blood pressure increases the workload on the heart. This extra strain can cause the heart to enlarge and weaken over time, ultimately impairing its ability to pump blood effectively.

• Heart valve problems: Damaged or faulty heart valves can disrupt normal blood flow, placing additional strain on the heart and leading to heart failure.

• Cardiomyopathy: This refers to inherited or acquired conditions that damage the heart muscle. Such damage reduces the heart's ability to pump blood effectively, contributing to heart failure.

• Arrhythmias: Abnormal heart rhythms can affect the heart's pumping efficiency. These irregularities can lead to heart failure if not properly managed.

• Other chronic conditions: Additional factors, such as diabetes, thyroid disorders, obesity, or the buildup of iron or protein in the body, can also contribute to the development of heart failure. Managing these conditions is essential to reducing the risk of heart failure.

Several factors can increase an individual's risk of developing heart failure, including:

• Age (65 or older)

• Family history of heart failure

• Smoking

• Obesity

• Diabetes

• High blood pressure

• Coronary artery disease

• Previous heart attack

• Valvular heart disease

• Congenital heart defects

• Certain medications (e.g., chemotherapy medicines)

Who's at Risk?

Several groups have a higher risk of developing heart failure, including:

• Old age

• High blood pressure or hypertension

• Coronary artery disease

• Diabetes

• Being overweight or obese

• Smoking, tobacco use, and excessive alcohol consumption

• Those who have suffered a previous heart attack or myocardial infarction

Heart failure can lead to various complications that affect multiple organs and systems in the body. Some of these complications include:

• Cardiac complications: These may include irregular heart rhythms or arrhythmias, such as atrial fibrillation and ventricular tachycardia. The increased workload on the heart can damage the heart valves, reducing their efficiency and leading to further cardiovascular issues.

• Renal complications: Renal complications are common due to reduced blood flow to the kidneys, which can result in kidney damage or failure. This may necessitate dialysis or even a kidney transplant.

• Liver complications: The liver can also be affected in individuals with heart failure, as fluid buildup may put extra pressure on the organ. This can lead to scarring (fibrosis) and impaired liver function, complicating the overall management of heart failure.

• Respiratory complications: Respiratory complications, such as pulmonary oedema, occur when fluid accumulates in the lungs, making breathing difficult. This condition is referred to as pulmonary congestion and can lead to significant respiratory distress.

• Musculoskeletal complications: Heart failure can impact muscle and fat metabolism, resulting in musculoskeletal complications like unintentional weight loss and muscle weakness. These changes can further reduce a patient's ability to engage in physical activity.

• Thromboembolic complications: Thromboembolic complications, including stroke and other thromboembolic events, can arise from low cardiac output and conditions like atrial fibrillation. These complications pose a significant risk and require careful monitoring and management.

Preventing heart failure involves adopting a healthy lifestyle and managing risk factors. Some of the preventative measures include:

• Maintain a balanced diet: Consuming a diet low in saturated fats, trans fats, and sodium can significantly contribute to heart health. Incorporating plenty of fruits, vegetables, whole grains, and lean proteins is essential for overall cardiovascular well-being.

• Engage in regular exercise: Aim for at least 150 minutes of moderate-intensity aerobic activity each week. Regular exercise strengthens the heart muscle, improves circulation, and enhances overall cardiovascular health.

• Manage stress: Utilising relaxation techniques, such as meditation, yoga, or deep breathing exercises, can help reduce stress levels, which is beneficial for heart health.

• Control underlying health conditions: Keeping blood pressure, cholesterol, and blood sugar levels within a healthy range is crucial in preventing heart failure. If prescribed, it’s important to take medications as directed by a doctor to manage these conditions effectively.

• Avoid smoking and limit alcohol consumption: Quitting smoking and reducing alcohol intake are critical steps in lowering the risk of heart failure and improving overall cardiovascular health.

• Regular check-ups: For individuals with a family history of heart failure or other heart diseases, scheduling regular check-ups with a cardiologist can help detect early signs and allow for timely intervention.

Diagnosing heart failure involves a combination of physical examination, medical history review, and various tests. These include:

• Physical examination: During the physical exam, your doctor will check for signs of fluid buildup, such as swollen ankles or crackles in your lungs, and listen to your heart for abnormal sounds that may indicate heart valve problems or an irregular heartbeat.
• Blood tests: These can help identify underlying conditions that may contribute to heart failure, such as anaemia or thyroid problems.
• Natriuretic peptide testing (BNP or NT‑proBNP): These blood tests help support the diagnosis of heart failure and are useful in distinguishing heart failure from other causes of breathlessness, especially in the acute setting (McDonagh et al., 2021).
• Electrocardiogram (ECG): This non-invasive test records the electrical activity of your heart and can detect irregularities in heart rhythm or signs of a previous heart attack.
• Echocardiogram: This ultrasound test provides detailed images of your heart, allowing your doctor to assess its size, structure, and function.
• Stress test: This test involves exercising on a treadmill or stationary bike while your heart's response is monitored, helping to identify coronary artery disease or other heart problems.
• Cardiac catheterisation: In some cases, a thin, flexible tube called a catheter may be inserted into a blood vessel and guided to your heart to measure pressure and assess blood flow.

The treatment of heart failure includes medications, device-based interventions, lifestyle modifications, and surgery to alleviate symptoms, enhance heart function, reduce hospitalisations, and improve overall quality of life (McDonagh et al., 2021). Here are the treatment options for heart failure:

1. Inotropic Medications

Inotropic agents are reserved for specific situations, such as advanced stages of heart failure with low cardiac output or during acute decompensation, and are usually used under specialist supervision in hospital settings. These agents increase the force of heart muscle contraction.

• Digoxin: Enhances the pumping ability of the heart and helps control ventricular rate in atrial fibrillation; in chronic heart failure, it is generally used as add‑on therapy in selected patients with persistent symptoms despite guideline‑directed medical therapy.
• Amrinone: Phosphodiesterase inhibitors (e.g., milrinone) improve cardiac output and reduce vascular resistance, providing short-term support in severe cases of decompensated heart failure, typically in intensive care.
• Dopamine: Used in carefully titrated intravenous doses in critical care to support blood pressure and cardiac output in selected patients with shock or severe decompensated heart failure.

2. Diuretics

Loop diuretics (such as furosemide) are the cornerstone for managing fluid overload, while thiazide or thiazide‑like diuretics may be added in selected patients to augment diuresis or control blood pressure.

• Frusemide: A loop diuretic that provides rapid and potent relief from congestion, especially in acute settings.
• Chlorthalidone: A thiazide-like diuretic effective in managing chronic volume overload and controlling blood pressure.
• Hydrochlorothiazide: Often used in mild heart failure or in combination with loop diuretics to enhance fluid removal.

3. ACE Inhibitors

Angiotensin-converting enzyme inhibitors are fundamental in reducing disease progression, improving symptoms, and increasing survival.

• Enalapril: Lowers blood pressure and eases the heart’s workload by dilating blood vessels, commonly used in both acute and chronic management.
• Lisinopril: A once-daily ACE inhibitor that helps prevent cardiac remodelling and reduce hospitalisations in heart failure patients.

4. Beta Adrenergic Blockers

Beta-blockers are essential for long-term management, especially in patients with reduced ejection fraction. Guidelines specifically recommend bisoprolol, carvedilol, or metoprolol succinate for patients with HFrEF, because these agents have demonstrated mortality and hospitalisation benefits in clinical trials. They improve heart function, reduce arrhythmias, and enhance survival.

• Metoprolol: Metoprolol succinate (extended‑release): A cardioselective beta‑blocker with strong evidence for improving survival, reducing hospitalisations, and improving symptoms in HFrEF.
• Propranolol: A non‑selective beta‑blocker rarely used specifically for heart failure; it may be prescribed for other conditions such as tremor, migraine, or anxiety in selected patients.
• Carvedilol: Provides both beta and alpha-blockade, helping to lower blood pressure and improve heart output in chronic heart failure.
• Nebivolol: Offers selective beta-blockade with added vasodilation, making it useful in hypertensive heart failure patients.

5. Aldosterone Blockers

These agents reduce fluid retention, prevent myocardial fibrosis, and improve survival in advanced heart failure.

• Spironolactone: A potassium-sparing diuretic that blocks aldosterone, easing symptoms and lowering hospitalisation risk.
• Eplerenone: A selective aldosterone receptor blocker with fewer endocrine side effects, ideal for long-term use in heart failure.

6. SGLT2 Inhibitor:

Sodium–glucose cotransporter‑2 (SGLT2) inhibitors are now a core component of guideline‑directed therapy for HFrEF and have benefits across the spectrum of ejection fraction (McDonagh et al., 2021).

• Dapagliflozin / Empagliflozin: These agents reduce heart failure hospitalisations and cardiovascular mortality in patients with HFrEF, regardless of whether they have diabetes, and are also beneficial in selected patients with HFmrEF or HFpEF.

7. Venodilators

Venodilators relieve heart failure symptoms by reducing preload and easing the strain on the heart.

• Glyceryl Trinitrate: Acts rapidly to dilate veins and arteries, providing quick relief from angina and pulmonary congestion.
• Isosorbide Dinitrate: A long-acting nitrate that improves exercise tolerance and reduces breathlessness in chronic heart failure.
• Hydralazine: A direct vasodilator that is often combined with nitrates for patients intolerant to ACE inhibitors or ARBs.
• Nitroprusside: An intravenous vasodilator used in intensive care to manage severe decompensated heart failure with markedly elevated blood pressure or acute pulmonary oedema, requiring close haemodynamic monitoring.

8. Combined Treatment Approaches

Some therapies combine two or more mechanisms for superior efficacy, especially in patients not adequately managed with standard therapy.

• Sacubitril + Valsartan: This angiotensin receptor–neprilysin inhibitor (ARNI) enhances natriuretic peptides while suppressing the renin–angiotensin system, shown to significantly reduce mortality and hospitalisation. In patients with symptomatic HFrEF who tolerate an ACE inhibitor or ARB, switching to sacubitril/valsartan is recommended to further reduce mortality and hospitalisations.
• Hydralazine + Isosorbide Dinitrate: Particularly effective in African-American patients with heart failure, this fixed-dose combination helps improve survival and functional status.

9. Devices

When medications are no longer sufficient, device-based therapies can dramatically improve heart performance and reduce complications.

• Implantable Cardioverter Defibrillators (ICDs): Prevent sudden cardiac death by correcting dangerous arrhythmias in patients with reduced ejection fraction.
• Cardiac Resynchronisation Therapy (CRT): Coordinates heart chamber contractions to enhance pumping efficiency, used in patients with electrical dyssynchrony.
• Left Ventricular Assist Devices (LVADs): Mechanical pumps that support heart function in end-stage heart failure, often used as a bridge to transplant or as destination therapy.

10. Surgery

Surgical procedures are considered when symptoms persist despite other treatments. CABG improves blood flow in those with blocked arteries, valve repairs or replacements address mechanical issues, and heart transplantation may be needed in end-stage heart failure when other treatments are no longer effective.

It's important to seek medical attention if you experience any signs or symptoms of heart failure, such as:

• Shortness of breath, especially when lying down or with minimal exertion

• Persistent coughing or wheezing

• Swelling in the feet, ankles, or legs

• Rapid or irregular heartbeat

• Fatigue and weakness

• Reduced ability to exercise

• Rapid weight gain from fluid retention

• Abdominal swelling

• Difficulty concentrating or decreased alertness

If you have been diagnosed with heart failure, it's crucial to attend regular follow-up appointments with your doctor and report any changes in your symptoms or overall health.

• Heart failure is a complex condition that requires a multifaceted approach to management, including lifestyle changes, medications, device therapies, and sometimes surgery.

• Lifestyle modifications, such as reducing sodium intake, quitting smoking, maintaining a healthy weight, and engaging in regular physical activity, are essential in managing heart failure.

• Medications, including ACE inhibitors, ARBs, beta-blockers, diuretics, aldosterone antagonists, and SGLT2 inhibitors, play a crucial role in treating heart failure and improving outcomes.

• Device therapies, like ICDs, CRT, and LVADs, may be recommended for some patients with heart failure.

• Surgical options, such as CABG, valve repair or replacement, and heart transplantation, are typically reserved for patients who do not respond to other treatments.

• It's important to seek medical attention if you experience any signs or symptoms of heart failure and to attend regular follow-up appointments if you have been diagnosed with the condition.