Heart Failure: Symptoms, Types, Diagnosis and Treatment
Author: Dr. Kulin Sheth, MD, DrNB Cardiology, Interventional Cardiologist
Medically reviewed by: Dr. Kulin Sheth, MD, DrNB Cardiology, Interventional Cardiologist
Last medically reviewed: 8 October 2026
Heart failure is a medical condition in which the heart cannot pump blood effectively enough, or cannot fill normally, to meet the body's needs.
Heart failure does not mean that the heart has stopped working.
It is a clinical syndrome with many possible causes, including coronary artery disease, previous heart attack, high blood pressure, heart valve disease, cardiomyopathy and abnormal heart rhythms. The underlying cause and type of heart failure determine which treatments are appropriate.
Modern treatment can significantly reduce symptoms, improve quality of life, reduce hospitalisations and, in many patients, improve survival. Some patients also experience substantial recovery of heart function when the underlying cause is identified and treated.
What is heart failure?
Heart failure occurs when a structural or functional problem with the heart results in symptoms or signs such as breathlessness, fatigue or fluid retention.
The problem may involve:
Reduced contraction: the heart does not squeeze strongly enough.
Impaired relaxation or filling: the heart becomes stiff and does not fill normally.
Abnormal heart rhythms: an arrhythmia can reduce the heart's ability to pump effectively.
Valve disease: a narrowed or leaking valve can place an excessive workload on the heart.
Heart muscle disease: cardiomyopathies and other myocardial disorders can impair cardiac function.
Structural heart disease: congenital or acquired abnormalities can contribute to heart failure.
Heart failure can affect the left side of the heart, the right side, or both.
It may develop gradually over months or years, or become apparent suddenly because of an acute event such as a heart attack, severe arrhythmia, uncontrolled blood pressure or acute valve disease.
What are the different types of heart failure?
Doctors commonly classify heart failure according to left ventricular ejection fraction (LVEF), together with the patient's symptoms, clinical stage and underlying cause.
Ejection fraction is the percentage of blood ejected from the left ventricle with each heartbeat. It is usually measured using an echocardiogram.
| Type | Ejection fraction | What it means |
|---|---|---|
| HFrEF — heart failure with reduced EF | ?40% | The left ventricle has reduced systolic pumping function. |
| HFmrEF — heart failure with mildly reduced EF | 41–49% | Pumping function is mildly reduced. |
| HFpEF — heart failure with preserved EF | ?50% | The EF is preserved, but the patient has heart failure due to abnormal cardiac function, often involving impaired relaxation or elevated filling pressures. |
| HFimpEF — heart failure with improved EF | Previous EF ?40%, subsequently >40% | Heart function has improved with treatment, but this does not necessarily mean that the underlying disease has disappeared. |
A normal or preserved ejection fraction does not automatically mean that there is no heart failure. Patients with HFpEF can have significant symptoms despite an EF of 50% or higher.
Conversely, a reduced ejection fraction on an echocardiogram does not by itself establish the complete diagnosis. Doctors interpret the EF alongside symptoms, examination findings, imaging and other investigations.
What causes heart failure?
Coronary artery disease and heart attack
Blocked coronary arteries can reduce blood supply to the heart muscle. A heart attack can permanently damage part of the heart muscle and reduce its pumping ability.
Patients with suspected coronary artery disease may require coronary angiography and angioplasty or other forms of coronary assessment depending on their symptoms, anatomy and clinical risk.
High blood pressure
Long-standing uncontrolled hypertension makes the heart work against higher pressure.
Over time, the heart muscle can become thickened and stiff and, in some patients, eventually become weakened.
See High Blood Pressure and Heart Health for more information.
Heart valve disease
Severe narrowing or leakage of a heart valve can place an abnormal workload on the heart.
Depending on the valve involved, its severity and the patient's surgical risk, treatment may include surgical heart valve repair or replacement, TAVI/TAVR or transcatheter mitral valve repair with MitraClip.
Cardiomyopathy
Cardiomyopathies are diseases of the heart muscle. They may be inherited, associated with infection or inflammation, related to alcohol or certain medications, or occur without an identifiable cause.
Abnormal heart rhythms
Atrial fibrillation and other sustained rapid or irregular rhythms can contribute to heart failure.
In some patients, controlling the heart rate or restoring and maintaining an appropriate rhythm can improve cardiac function.
Apollo CVHF provides arrhythmia and ablation services for selected rhythm disorders.
Diabetes and metabolic disease
Diabetes is strongly associated with cardiovascular disease and can contribute to the development and progression of heart failure.
See Diabetes and Heart Health for more information.
Other causes
Other conditions that may contribute include congenital heart disease, infiltrative diseases, certain toxic exposures, some cancer treatments and inflammatory or other disorders affecting the heart muscle.
Because the cause matters, treatment should not stop at identifying a low ejection fraction.
The next question is why the heart is failing and whether that cause can be treated.
What are the symptoms of heart failure?
Symptoms vary considerably between patients and depend on the type and severity of heart failure.
Common symptoms include:
Breathlessness during physical activity
Breathlessness when lying flat
Waking at night because of breathlessness
Reduced exercise tolerance
Persistent fatigue
Swelling of the feet, ankles or legs
Abdominal swelling or a feeling of fullness
Rapid or irregular heartbeat
Persistent cough or wheezing in some patients
Unexpected weight gain caused by fluid retention
Symptoms may initially be subtle.
A person may simply notice that activities that were previously easy—such as climbing stairs or walking a particular distance—now cause unusual breathlessness or fatigue.
When is breathlessness an emergency?
Not every episode of breathlessness is caused by heart failure.
However, new, severe or rapidly worsening breathlessness requires prompt medical assessment.
Seek emergency medical attention for:
Severe breathlessness at rest
Sudden worsening of breathlessness
Chest pain or pressure
Fainting or near-fainting
Severe weakness or confusion
Blue or grey lips or skin
Rapid deterioration in someone already diagnosed with heart failure
Acute heart failure can be life-threatening and may require hospital treatment.
If symptoms are severe or sudden, do not attempt to determine the cause yourself.
How is heart failure diagnosed?
There is no single test that diagnoses every case of heart failure.
Doctors combine the patient's medical history and physical examination with cardiac imaging, blood tests and other investigations.
Echocardiogram
An echocardiogram is one of the most important investigations in the assessment of heart failure.
It can evaluate:
Left ventricular ejection fraction
Heart chamber size
Heart muscle function
Heart valve structure and function
Right-sided heart function
Other structural abnormalities
Apollo CVHF provides 2D, 3D and advanced echocardiography, including global longitudinal strain (GLS) when clinically appropriate.
Blood tests
BNP and NT-proBNP are natriuretic peptides that can support the diagnosis and assessment of heart failure.
They must, however, be interpreted in context. Levels can be affected by factors such as kidney disease, atrial fibrillation and body weight.
Other blood tests may assess kidney function, electrolytes, blood count, thyroid function, glucose and other potential contributors or complications.
Electrocardiogram
An ECG can identify:
Abnormal heart rhythms
Conduction abnormalities
Evidence of previous or ongoing myocardial injury
Electrical patterns that may influence decisions about device therapy
Chest X-ray
A chest X-ray can provide supporting information, including evidence of pulmonary congestion or other causes of breathlessness.
It is not sufficient by itself to diagnose heart failure.
Coronary assessment
When coronary artery disease is suspected, doctors may use:
Stress testing or other functional assessment in selected patients
The appropriate investigation depends on the patient's symptoms, risk factors, clinical condition and previous investigations.
Other investigations
Some patients require additional tests such as:
Cardiac MRI
Stress echocardiography
Rhythm monitoring
Advanced laboratory testing
Assessment for specific cardiomyopathies
Evaluation for infiltrative or inflammatory heart disease
The diagnostic process is therefore tailored to the individual patient rather than based on a single test.
How is heart failure treated?
Treatment depends on:
Ejection fraction
Underlying cause
Severity of symptoms
Blood pressure
Kidney function
Heart rhythm
Other medical conditions
Previous hospitalisations
Presence of significant coronary or valve disease
The goals are to relieve symptoms, prevent deterioration and hospitalisation, improve quality of life and, where evidence supports it, reduce cardiovascular mortality.
1. Guideline-directed medical therapy
For patients with HFrEF, modern treatment commonly includes four foundational medication groups:
| Medication group | General role |
|---|---|
| ARNI, or ACE inhibitor/ARB when appropriate | Reduces harmful neurohormonal activation and cardiovascular events |
| Evidence-based beta-blocker | Reduces sympathetic stress on the heart and improves outcomes |
| Mineralocorticoid receptor antagonist (MRA) | Improves outcomes in appropriately selected patients |
| SGLT2 inhibitor | Reduces heart-failure hospitalisation and cardiovascular risk, with benefits that extend beyond patients with diabetes |
Current treatment approaches emphasise establishing these foundational therapies early when clinically appropriate and then adjusting doses according to tolerance.
Blood pressure, kidney function, potassium levels, heart rate, congestion and other factors influence medication selection and dosing.
What about diuretics?
Diuretics are frequently used when heart failure causes fluid retention.
They can reduce:
Leg swelling
Breathlessness caused by congestion
Abdominal fluid accumulation
Other symptoms associated with excess fluid
Diuretics primarily control congestion and symptoms. They are not a substitute for disease-modifying therapies in patients who are candidates for them.
2. Treatment according to ejection fraction
HFrEF
Patients with HFrEF generally benefit from the four foundational medication groups described above, provided there are no contraindications.
Additional treatment may be required depending on symptoms, heart rhythm, kidney function, blood pressure and other clinical factors.
HFmrEF
Patients with mildly reduced EF may benefit from several therapies used in HFrEF, although the strength of evidence differs between medication classes.
SGLT2 inhibitors have an established role in appropriate patients with HFmrEF.
HFpEF
HFpEF is particularly important because a preserved EF does not mean that heart failure is benign.
Treatment may include:
Controlling congestion
Managing blood pressure
SGLT2 inhibitor therapy where appropriate
Treating atrial fibrillation and other arrhythmias
Managing coronary artery disease
Treating diabetes, obesity and other relevant comorbidities
Identifying and treating specific causes of elevated filling pressures or structural heart disease
HFimpEF
When a patient previously had an EF of 40% or below and subsequently improves to above 40%, this is termed heart failure with improved ejection fraction (HFimpEF).
Improvement in EF is excellent news, but it does not necessarily mean that the underlying disease has been permanently cured.
In appropriate patients, guideline-directed therapy is generally continued because stopping treatment can allow heart failure to recur.
3. Treating the underlying cause
Coronary artery disease
Some patients with heart failure have significant coronary artery disease that requires revascularisation.
Depending on coronary anatomy and the overall clinical picture, treatment may involve:
Revascularisation is not automatically required simply because coronary blockages are present.
The cardiology team must determine whether intervention is likely to benefit the individual patient.
Valve disease
Severe valve disease can contribute to heart failure.
Depending on the valve, anatomy and surgical risk, treatment may include:
Arrhythmias
Atrial fibrillation and other arrhythmias may worsen heart failure.
Treatment can include rate control, rhythm control, cardioversion, catheter ablation in selected patients and anticoagulation when indicated.
See Arrhythmia and Ablation at Apollo CVHF.
4. Device therapy
Some patients with heart failure benefit from an implanted cardiac device.
Implantable cardioverter-defibrillator (ICD)
An ICD can detect dangerous ventricular arrhythmias and deliver therapy when required.
It is considered in selected patients at increased risk of sudden cardiac death, based on factors such as ejection fraction, symptoms, underlying disease and duration of appropriate medical treatment.
Cardiac resynchronisation therapy (CRT)
In selected patients with reduced EF and specific electrical conduction abnormalities, the ventricles may not contract in a coordinated manner.
CRT is designed to synchronise ventricular contraction.
Not every patient with a low EF needs CRT. Eligibility depends on factors including the ECG and QRS characteristics, rhythm, EF, symptoms and underlying disease.
Apollo CVHF provides pacemaker, ICD and CRT device therapy where clinically indicated.
5. Advanced heart failure
A smaller group of patients develops advanced heart failure despite appropriate medication, treatment of the underlying cause and device therapy.
These patients may require assessment by a specialist heart-failure team to determine whether advanced therapies are appropriate.
Depending on the individual clinical situation, advanced heart-failure management can include evaluation for mechanical circulatory support or heart transplantation.
These treatments are highly specialised and are not appropriate for most people with heart failure.
Living with heart failure
Heart failure is usually a long-term condition, but a diagnosis does not mean that a person cannot live an active and meaningful life.
Take medications consistently
Do not stop or change heart-failure medication without discussing it with your doctor, even if you feel well.
Some medications protect the heart over the long term even when they do not produce an obvious immediate improvement in symptoms.
Monitor your symptoms and weight
Patients may be advised to weigh themselves regularly, often at the same time each morning.
A sudden increase in weight may indicate fluid accumulation.
There is no single weight-change threshold that applies to everyone, so follow the action plan provided by your treating team.
Follow an appropriate diet
Many patients benefit from reducing excessive sodium intake and avoiding heavily processed, salty foods.
Fluid restriction is not automatically necessary for every patient. If fluid restriction is appropriate, the treating team should specify the recommended amount.
Stay physically active
Appropriate physical activity can improve exercise capacity and quality of life.
The amount and intensity of exercise should depend on the severity and stability of heart failure. Some patients may benefit from supervised cardiac rehabilitation.
Control associated conditions
Good management of other health problems is an important part of heart-failure care.
These may include:
High blood pressure
Diabetes
High cholesterol
Obesity
Kidney disease
Sleep apnoea
Atrial fibrillation and other arrhythmias
Avoid smoking and discuss alcohol
Smoking cessation is strongly recommended.
Alcohol intake should be discussed with the treating cardiologist because recommendations depend on the underlying cause and severity of heart failure.
Why regular follow-up matters
Heart failure management is not a one-time decision.
During follow-up, the cardiology team may assess:
Symptoms and exercise tolerance
Blood pressure and heart rate
Body weight and fluid status
Kidney function
Electrolytes
Medication tolerance
Heart rhythm
Ejection fraction and other cardiac imaging findings
Whether device therapy or another intervention has become appropriate
Treatment often needs to be adjusted over time.
A patient who feels stable should still continue scheduled follow-up because the purpose of treatment is not simply to respond to symptoms, but also to prevent future deterioration.
How Apollo CVHF approaches heart failure care
Apollo CVHF Hospital is a dedicated cardiovascular centre in Ahmedabad focused on the diagnosis and treatment of cardiovascular disease.
Patients with suspected or established heart failure may require assessment across multiple cardiovascular disciplines depending on the underlying cause.
Relevant services include:
These services are not required for every patient with heart failure. The appropriate treatment depends on the individual's diagnosis, anatomy, severity, symptoms, comorbidities and response to medical therapy.
For patients who have already been advised a cardiac procedure or have questions about an existing report, cardiology second opinion can help clarify the diagnosis and available treatment options.
Frequently asked questions about heart failure
Can heart failure be cured?
It depends on the cause.
Some forms of heart failure can improve substantially when an underlying cause is treated, and some patients experience significant recovery of heart function.
However, improvement in ejection fraction does not necessarily mean that the underlying disease has disappeared. Many patients require ongoing treatment and follow-up.
Is heart failure the same as a heart attack?
No.
A heart attack occurs when blood flow to part of the heart muscle is suddenly reduced or blocked, usually because of a coronary artery blockage.
Heart failure is a clinical syndrome in which the heart has abnormal function that results in symptoms or signs.
A heart attack can cause heart failure, but the two conditions are not the same.
Can someone have heart failure with a normal ejection fraction?
Yes.
HFpEF occurs when a patient has heart failure despite a preserved ejection fraction.
The diagnosis depends on the overall clinical picture and evidence of abnormal cardiac function or elevated filling pressures, not simply the EF number.
Does a low ejection fraction always mean severe heart failure?
No.
Ejection fraction is important, but it is only one part of the assessment.
Symptoms, congestion, exercise capacity, underlying cause, heart rhythm, kidney function, blood pressure and other findings all contribute to determining severity and treatment.
Can angioplasty treat heart failure?
Angioplasty can treat coronary artery blockages in appropriately selected patients.
It is not a treatment for heart failure itself in every patient.
If coronary artery disease is contributing to heart dysfunction, the cardiology team determines whether angioplasty, bypass surgery, medical treatment or another approach is most appropriate.
Does every patient with heart failure need a pacemaker?
No.
Some patients require a standard pacemaker because of a slow or abnormal heart rhythm.
Others may qualify for CRT because of a specific combination of reduced heart function, symptoms and electrical conduction abnormalities.
An ICD serves a different purpose: protecting selected patients against potentially life-threatening ventricular arrhythmias.
Should heart-failure patients restrict fluids?
Not automatically.
Some patients with significant congestion may be given a fluid restriction, while others do not require one.
Fluid recommendations should be individualised according to the severity of heart failure, kidney function, sodium levels and other clinical factors.
What should I do if my breathing suddenly becomes worse?
Sudden or severe breathlessness can be a medical emergency.
If it is accompanied by chest pain, fainting, severe weakness, confusion or severe breathlessness at rest, seek emergency medical care immediately.
When should you see a cardiologist?
A cardiology assessment is appropriate if you have:
Unexplained or progressive breathlessness
Swelling of the legs or abdomen
Reduced exercise tolerance
Persistent fatigue
Breathlessness when lying down or waking at night
A previously abnormal echocardiogram
A significantly reduced ejection fraction
Previous heart attack or significant coronary artery disease
Significant valve disease
Cardiomyopathy
A newly diagnosed arrhythmia
Recurrent hospitalisation for breathlessness or fluid overload
Early assessment can help identify the underlying cause and determine whether the condition can be treated or its progression reduced.
Key takeaways
Heart failure does not mean that the heart has stopped.
It is a clinical syndrome caused by structural or functional abnormalities of the heart.
Heart failure can occur with reduced, mildly reduced or preserved ejection fraction.
Finding the cause is as important as measuring the ejection fraction.
Modern treatment includes evidence-based medications, treatment of underlying coronary or valve disease, device therapy for selected patients, and long-term lifestyle and follow-up care.
Not every patient with heart failure needs angioplasty, bypass surgery, a pacemaker or another procedure.
Sudden or severe breathlessness, chest pain or fainting requires urgent medical assessment.
With appropriate treatment and follow-up, many people with heart failure can live active lives for many years.
References
Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure. Circulation. 2022;145.
McDonagh TA, Metra M, Adamo M, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. European Heart Journal. 2021;42:3599-3726.
McDonagh TA, Metra M, Adamo M, et al. 2023 Focused Update of the 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. European Heart Journal. 2023;44:3627-3639.
Medical disclaimer
This article is intended for general educational purposes and does not replace an individual medical consultation.
Heart-failure treatment must be personalised according to the patient's symptoms, examination findings, ejection fraction, underlying cause, kidney function, blood pressure, heart rhythm, other medical conditions and response to treatment.
Do not start, stop or change prescription medication without medical advice.
Author: Dr. Kulin Sheth, MD, DrNB Cardiology, Interventional Cardiologist
Medically reviewed by: Dr. Kulin Sheth, MD, DrNB Cardiology, Interventional Cardiologist
Last medically reviewed: 8 October 2026
