What is an Acute Heart Failure?

Introduction

Acute heart failure is a sudden and potentially life-threatening condition¹. It is one of the leading causes of hospitalisation among adults over the age of 65, with millions of cases diagnosed each year^1,2.

Despite how frequently doctors encounter it, each case of acute heart failure is unique, and outcomes can vary widely from person to person¹. As its prevalence continues to rise, acute heart failure is not only a major medical concern but also a significant contributor to global healthcare costs^1,2.

In this article, we will explore what acute heart failure is, understand its underlying causes and risk factors, examine current management strategies, and discuss ways it can be avoided.

What is Acute Heart Failure?

Acute heart failure is a sudden and serious condition in which the heart stops pumping enough oxygen-rich blood to meet the body’s demands. It typically results from a rapid decline in heart function, often triggered by an underlying heart issue or the worsening of existing heart disease. This leads to a significant drop in the heart’s ability to circulate blood effectively, causing a range of symptoms that require immediate medical attention^1,3.

Unlike chronic heart failure, which develops gradually over time and is managed with long-term acute heart failure treatment strategies, acute heart failure happens quickly and can be life-threatening. Though the changes in heart function may begin subtly, they progress until the heart can no longer maintain adequate blood flow in both cases^1,4.

Types of Acute Heart Failure

Acute heart failure can occur in two ways^1,3:

De Novo Heart Failure

This may be the first presentation of heart failure in someone previously undiagnosed with any heart-related conditions.

Acute Decompensated Heart Failure

This may represent a sudden worsening of symptoms in someone with a previously diagnosed heart condition like coronary artery disease (narrowed or blocked arteries of the heart).

In both cases, the primary problem is that the heart becomes congested and struggles to keep up with the body’s circulatory needs.

Symptoms

The most common indication ofheart failure is not being able to breathe deeply (shortness of breath). Besides this, people often show the following acute heart failure symptoms:

• Laboured or heavy breathing
• A feeling of suffocation or air hunger
• Difficulty breathing when lying flat (which may require propping up with pillows)
• Sensation of tightness/pressure in the chest

In addition to breathing difficulties, acute heart failure can present with a variety of other symptoms, including¹:

• Irregular or rapid heartbeat (arrhythmia)
• Persistent coughing
• Chest pain or discomfort (may vary in intensity)
• Fainting or sudden loss of consciousness
• Swelling in the legs or arms (oedema)

These symptoms can appear suddenly and escalate quickly, making early recognition and urgent medical evaluation critical for effective treatment.

Causes

Acute heart failure can be triggered by a wide range of medical conditions and underlying health issues that place excessive stress on the heart, impairing its ability to function effectively. Here are some frequently observed/common causes of heart failure¹:

• Uncontrolled high blood pressure (hypertension)
• Diabetes
• Hyperthyroidism (excess thyroid hormone production)
• Viral infections
• Abnormal heart rhythms (arrhythmias)
• Coronary artery disease
• Cardiomyopathy (thickening of heart muscles)
• Advanced kidney disease
• Pulmonary embolism (blood clots in the lungs)
• Diseases of the heart valves
• Chronic alcohol abuse
• Sleep apnoea (breathing obstruction while sleeping)
• Stroke

Risk Factors

Many factors could increase your likelihood of developing acute heart failure. These include⁵:

• Age (people over the age of 65)
• Genetics and family history of heart failure
• Chronic health conditions such as obesity, high blood pressure, diabetes, etc.
• Cancer treatments such as chemotherapy and radiation

If you are already at risk for or living with a heart disease, some choices and habits can rapidly worsen your condition and trigger acute heart failure. These may include^1,5:

• Skipping or improperly taking prescribed medications
• Consuming too much salt
• Not restricting fluid intake (if advised)
• Using alcohol, recreational drugs, or other harmful substances
• Smoking
• Taking nonsteroidal anti-inflammatory drugs (NSAIDs)

Diagnosis and Tests

The diagnostic process for heart failure begins with a detailed clinical evaluation, which includes¹:

• Reviewing Your Medical History: Your doctor will ask about any personal or family history of heart disease, as well as other conditions like high blood pressure, diabetes, or kidney disease. They’ll also inquire about your use of tobacco, alcohol, or recreational drugs, along with any medications or supplements you may be taking.
• Conducting a Physical Examination: This helps assess your overall condition and identify signs of fluid buildup, such as swelling in your legs or abdomen. Your doctor will listen for abnormal heart or lung sounds.

To confirm the diagnosis and guide treatment, a series of diagnostic tests is typically performed. These tests provide detailed insights into how well your heart is functioning and whether other organs are affected¹:

• Electrocardiogram (ECG or EKG): Measures your heart’s electrical activity to detect signs of damage.
• Chest X-ray: Offers a visual of your heart and lungs, helping to detect fluid accumulation or lung congestion.
• Echocardiogram: An ultrasound of the heart that reveals how well the heart is pumping and whether the valves are functioning properly.
• Thoracic ultrasound: Focuses on the chest area to detect signs of oedema in the lungs.
• Coronary angiography: This procedure assesses for blockages and helps determine the condition and functioning of heart.
• B-type natriuretic peptide (BNP) blood test: Measures levels of specific hormones released by the heart when it is under stress or experiencing pressure changes.
• Basic metabolic panel (BMP): A set of blood tests that help in evaluating kidney function, electrolyte balance, and even thyroid health.

Management and Treatment

Acute heart failure is a medical emergency that requires immediate attention to restore oxygen levels and improve blood circulation throughout the body. Initial acute heart failure treatment may include⁷:

1. Angiotensin-Converting Enzyme Inhibitors (ACEIs)

They are first-line agents in the management of heart failure, helping to improve blood flow. Examples include:

• Captopril
• Enalapril
• Lisinopril
• Fosinopril
• Perindopril
• Quinapril
• Ramipril
• Trandolapril

2. Angiotensin II Receptor Blockers (ARBs)

These are alternatives to ACEIs in patients who are intolerant to ACEIs. Examples include:

• Candesartan
• Losartan
• Valsartan

3. Beta Blockers

Beta blockers control heart rate. Examples include:

• Bisoprolol
• Carvedilol
• Carvedilol CR (controlled release)
• Metoprolol succinate (extended release)

4. Loop Diuretics

These are used for symptomatic relief in patients with volume overload. Examples include:

• Furosemide
• Torsemide
• Bumetanide
• Ethacrynic acid (used in sulpha allergy)

5. Thiazide Diuretics (Used in Combination with Loop Diuretics)

They may be used as add-on therapy in cases of diuretic resistance to loop diuretics. Examples include:

• Metolazone
• Hydrochlorothiazide

6. Aldosterone Antagonists

These agents reduce mortality and hospitalisations in patients, especially those with fluid overload: Examples include:

• Spironolactone
• Eplerenone

7. Vasodilators

These are especially useful in patients who are intolerant to ACEIs/ARBs. Examples include:

• Hydralazine
• Isosorbide dinitrate
• Fixed-dose combination (Hydralazine/Isosorbide dinitrate)

8. Cardiac Glycoside (Digoxin)

It is used in selected patients to reduce hospitalisations and improve symptoms. Example:

• Digoxin

9. If Channel Inhibitor (Ivabradine)

It is used to reduce hospitalisations in patients with heart failure. Example:

• Ivabradine

10. Angiotensin Receptor-Neprilysin Inhibitor (ARNI)

They are used to lower strain on the heart. Example:

• Sacubitril/valsartan

Note: Dose titration should be individualised based on patient response, tolerance, renal function, and electrolyte levels. Regular follow-up and lab monitoring are essential.

At the same time, your doctor and his team will focus on treating the root cause of the acute episode. Although acute heart failure can’t be cured, it can be effectively managed with a combination of medications and sometimes surgical interventions.

Surgical interventions may include^1,6:

• Placing a stent (a small tube-like structure) or performing a surgery to improve blood flow to the heart muscle.
• Repairing damaged or malfunctioning heart valves to restore proper blood flow.
• Implanting a pacemaker to help regulate irregular heartbeats.
• Implanting a cardioverter defibrillator (ICD) to detect abnormal rhythms of the heart.
• Using a ventricular assist device (VAD) to support weakened heart function (often used as a bridge to heart transplantation).

In cases of end-stage heart failure where other acute heart failure treatments are no longer effective, a heart transplant (replacing the failing heart with a healthy donor heart) may be necessary.

Also Read: Everything to Know About Irregular Heartbeat (Arrhythmia)

Prevention

Taking some steps to protect your heart health could positively contribute to reducing your chances of developing or worsening heart failure. These include^1,8:

• Limiting sodium (salt) in the diet, as an excess might cause your body to retain fluid.
• Supporting a healthy body weight by following a nutritious diet that includes plenty of fruits and vegetables.
• Refraining from use of tobacco products. As an additional precautionary measure, also avoid going/visiting places where other people are smoking.
• Managing stress using relaxation techniques (such as deep breathing).
• Avoiding excessive alcohol use and illegal drugs.
• Engaging in regular physical activity (as advised/approved by your doctor).
• Prioritising restful sleep.
• Seeking treatment for diabetes and sleep disorders like sleep apnoea (as these may contribute to heart failure if left unmanaged).

Living With Acute Heart Failure

Managing acute heart failure doesn’t stop after a hospital stay, it becomes a part of daily life. With the right approach and support, many individuals live full, active lives while keeping their condition under control. Here is what you can do:

1. Sodium Monitoring

Avoid high-sodium foods like canned soups, processed meats, fast food, and frozen meals. Make a habit of reading food labels, this will help you to learn and identify hidden sources of salt⁸.

2. Medications

Your doctor will suggest medications to manage acute heart failure symptoms. Keep these points in mind during your medication course⁸:

• Take them at the same time each day.
• Watch for side effects such as dizziness, muscle cramps, irregular heartbeat, fatigue, or changes in mood.
• Notify your healthcare provider if you have any existing allergies or if you develop unexpected symptoms during your medication course.

3. Daily Weighing and Fluid Monitoring

Depending on your presenting symptoms and medical history, your doctor may adjust your fluid intake. This will be highly dependent on your body’s overall fluid balance. Tracking your weight is also a vital part of managing fluid retention^1,8:

• Weigh yourself every morning, using the same scale and similar clothing (before breakfast and after using the bathroom).
• Record your weight daily and watch for trends.
• Reach out to your doctor if you significantly gain weight (more than 1 to 1.5 kg/day or 2 kg/week).
• Contact your doctor if you notice that your clothes appear tighter than before. Also, let him know if you observe swelling in any body parts.

4. Long-Term Lifestyle and Emotional Support

Living with acute heart failure means making adjustments, but it doesn’t mean giving up a good quality of life:

• Follow your medication plan precisely.
• Monitor your symptoms.
• Attend all follow-up appointments.
• Eat heart-healthy meals.
• Stay physically active as advised.
• Avoid NSAIDs unless your doctor approves.

When to See a Doctor

Recognising warning signs of heart failure and reporting them early can avoid serious complications. Reach out to your healthcare provider if you observe the following⁸:

• Persistent fatigue or unusual weakness (even with minimal activity or rest).
• Shortness of breath, whether during physical activity, at rest, or especially when lying flat or waking up suddenly gasping for air.
• Wheezing or breathing difficulties.
• A lingering or worsening cough, which may be dry and hacking (accompanied by pink, frothy mucus).
• New (or even worsening) symptoms such as swelling in different body parts.
• Frequent nighttime urination, or a noticeable change in how often you need to urinate
• Unexplained weight gain or loss
• Bloating, pain, or tenderness in your abdomen
• Side effects from medications, such as dizziness or nausea
• Changes in the rhythm of your heart

Don’t hesitate to contact your provider if you’re unsure whether a symptom is serious.

Conclusion

Acute heart failure is a serious condition that requires immediate medical attention and ongoing care. Early detection of symptoms like shortness of breath, fatigue, and swelling could lead to prompt diagnosis and better outcomes. Managing underlying health issues, taking prescribed medications, and making heart-healthy lifestyle changes are key to prevention and long-term management. With the right care and habits, it’s possible to reduce your risk and improve your quality of life.

Frequently Asked Questions (FAQs)

References

1. Cleveland Clinic. Acute Heart Failure [Internet]. Cleveland Clinic; 2024 [cited 2025 Apr 14]. Available from: https://my.clevelandclinic.org/health/diseases/21686-acute-heart-failure
2. American Heart Association. Acute Heart Failure: Clinical Update. J Am Heart Assoc. 2023;12(5):e031745. doi:10.1161/JAHA.123.031745​. Available from: https://pubmed.ncbi.nlm.nih.gov/37889197/ 
3. Arrigo M, Jessup M, Mullens W, Reza N, Shah AM, Sliwa K, Mebazaa A. Acute heart failure. Nat Rev Dis Primers. 2020 Mar 5;6(1):16. doi: 10.1038/s41572-020-0151-7. PMID: 32139695; PMCID: PMC7714436. Available from: https://pubmed.ncbi.nlm.nih.gov/32139695/ 
4. Cleveland Clinic. Congestive Heart Failure: Symptoms, Stages & Treatment [Internet]. Cleveland Clinic; 2023 [cited 2025 Apr 14]. Available from: https://my.clevelandclinic.org/health/diseases/17069-heart-failure-understanding-heart-failure​
5. National Heart, Lung, and Blood Institute. Heart Failure – Causes and Risk Factors [Internet]. NHLBI; [updated 2022 Mar 24; cited 2025 Apr 14]. Available from: https://www.nhlbi.nih.gov/health/heart-failure/causes​
6. Čerlinskaitė K, Javanainen T, Cinotti R, Mebazaa A; Global Research on Acute Conditions Team (GREAT) Network. Acute Heart Failure Management. Korean Circ J. 2018 Jun;48(6):463-480. doi: 10.4070/kcj.2018.0125. PMID: 29856141; PMCID: PMC5986746. Available from: https://pubmed.ncbi.nlm.nih.gov/29856141/ 
7. Shah A, Gandhi D, Srivastava S, Shah KJ, Mansukhani R. Heart Failure: A Class Review of Pharmacotherapy. P T. 2017 Jul;42(7):464-472. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5481297/
8. MedlinePlus. Heart failure – fluids and diuretics [Internet]. U.S. National Library of Medicine; 2024 [cited 2025 Apr 14]. Available from: https://medlineplus.gov/ency/patientinstructions/000112.htm​

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