Understanding the early signs of heart failure

When we talk about the early signs of heart failure, it is often easy to dismiss them. Who hasn’t felt unusually tired after a long week? Or chalked up mild shortness of breath to a workout you skipped? But before these symptoms go unnoticed, they can be the subtle whispers of your heart asking for attention.

What is heart failure?

Contrary to what some might think, heart failure is often not a sudden medical event like a heart attack. It is a gradual, chronic condition that requires thoughtful, ongoing care. Essentially, the heart is not pumping blood as efficiently as it should, which can cause fluid to back up into the lungs and make breathing more difficult. For a visual depiction of how heart failure develops, this animation may be helpful.

Although all hearts age as we get older, many things can contribute to this weakening over time, increasing the “wear and tear” on your heart. If you have more than one of these conditions, your risk of heart failure could be greater.

• Heart disease (coronary artery disease)
• A previous heart attack, which weakens the heart’s ability to pump blood
• An abnormal heart valve, which can be present at birth or happens as a result of disease or infection
• Inflammation or damage to the heart muscle from drug and/or alcohol use, viral infections or other unknown causes
• Heart defects present at birth
• Severe lung disease like chronic obstructive pulmonary disease (COPD)
• High blood pressure (also known as hypertension)
• Diabetes
• Obesity
• Sleep apnea
• Abnormal heart rhythm (called arrhythmia)
• Cancer chemotherapy or radiation therapy

The 4 stages of heart failure

Heart failure does not happen all at once. It typically evolves through four stages. Understanding these can help you and your healthcare provider act early and effectively.

Stage A: At risk, but symptom-free

At this point, you do not show signs of heart disease. Yet conditions like high blood pressure, diabetes, obesity or a family history of heart trouble can place you in this “pre-heart failure” category. It is a key window where prevention matters most.

Stage B: Silent changes in the heart

There are still no noticeable symptoms, but imaging or tests might reveal structural heart changes. This subtle shift signals that something is changing under the surface.

Stage C: Symptoms emerge

The early signs of heart failure start to become difficult to ignore. You may notice limitations in daily activities, weight gain or nighttime breathing trouble.

Stage D: Progression to end-stage heart failure

At this stage, symptoms are persistent and often severe, limiting your daily life and potentially requiring hospitalization.

How to spot 6 early signs of heart failure

Identifying symptoms early on can make a big difference in managing heart failure, especially if you have known risk factors. Keep an eye out for the following:

1. Shortness of breath during activity, rest or even sleep. This may be especially noticeable when lying flat.
2. Swelling in ankles, feet, legs or abdomen. Your shoes may feel snug.
3. Persistent cough or wheezing, sometimes with white or blood-tinged mucus.
4. Mental fog or confusion, when you or someone close to you might notice feelings of disorientation, difficulty concentrating or unexplained memory loss.
5. Sudden weight gain, typically from fluid retention (a condition known as edema).
6. Unusual fatigue that makes everyday tasks, like climbing stairs or carrying groceries, feel unexpectedly exhausting.

If you have been experiencing any or a combination of these heart failure symptoms and are worried you may be experiencing heart failure, talk to your cardiologist, if you have one, or your primary care physician, who can refer you to a cardiologist for specialized care.

Want to learn more about your heart health? Take our heart health quiz.

Take action early: Healthy habits to support your heart

If any of these early signs of heart failure are making themselves known, you don’t have to face them alone. Early detection and treatment can slow progression, ease symptoms and preserve your quality of life.

Preventing or managing heart failure often begins with simple, healthy lifestyle choices, which include:

• Quitting smoking
• Keeping a healthy weight
• Managing stress
• Tracking fluid intake
• Limiting alcohol and caffeine
• Monitoring blood pressure and symptoms
• Following a heart-healthy diet 
• Prioritizing good sleep habits
• Staying active
• Avoiding tight clothing and extreme heat

These habits, combined with your healthcare provider’s guidance, can set you on the right path to a heart healthy future.

Ready to take control of your heart health? Download the heart failure treatment guide and book an appointment with a cardiologist today.