What is heart failure?
Heart failure is a condition that happens when your heart muscle works too hard over a long period of time. Your heart might be overworking for several reasons. Perhaps you have high blood pressure. Or maybe there’s plaque buildup in your arteries.
Eventually, your heart gets too tired to keep working as hard as it has been. The heart muscle itself starts to change. Then, it can no longer pump out as much blood and oxygen to the rest of your body.
What are the categories of heart failure?
There are two ways to group the severity of heart failure—by class (I, II, III, or IV) or by stage (A, B, C, or D). You might hear your healthcare providers talking about heart failure stages and classes, so here’s a summary of both.
Heart failure classes
The New York Heart Association (NYHA) Functional Classification groups the condition based on how severe your symptoms are and how much the symptoms disrupt your daily life activities.
NYHA Class 1 Symptoms
No limits on physical activity
Comfortable at rest
Normal physical activity does not cause fatigue or shortness of breath
NYHA Class II Symptoms
Slight limits of physical activity
Comfortable at rest
Normal physical activity may cause fatigue or shortness of breath
NYHA Class III Symptoms
Noticeable limits of physical activity
Comfortable at rest
Minimal physical activity causes fatigue or shortness of breath
NYHA Class IV Symptoms
Cannot comfortably carry on physical activity
Heart failure symptoms, even at rest
Any activity causes even more discomfort
Here are a few examples to help paint a picture for you. Say your neighbor Carol is retired and spends her time at home most days. She walks down her driveway to the mailbox around noon everyday. She doesn’t feel winded or out of breath once she gets the mail and sits back down in her chair. In fact, she never notices any shortness of breath or fatigue, but she has high blood pressure. Carol would probably be in NYHA Class I.
But if a simple activity like walking to and from the mailbox did make Carol feel tired or out of breath, Carol might be in NYHA Class II or III.
Heart failure stages
Heart failure stages were developed by the American Heart Association (AHA) and the American College of Cardiology (ACC). Stages A and B of heart failure are sometimes called pre-heart failure stages. If you’re in one of these two groups, it means you don’t have heart failure yet, but you’re at risk of developing it.
Stage A - You’re at risk of heart failure, but you don’t have any structural damage to your heart or heart failure symptoms.
Who has Stage A heart failure?
- People with:
High blood pressure
Diabetes
Obesity
Metabolic syndrome
Atherosclerosis (plaque buildup in the arteries)
- People using cardiotoxins, like many chemotherapy drugs, amphetamines, and malaria drugs
- People with a family history of cardiomyopathy (heart muscle disease)
Stage B - You’re at risk for heart failure and you do have structural heart damage, but you don’t have signs or symptoms of heart failure.
Who has Stage B heart failure?
- People with:
Previous heart attack
Changes to the size, shape, or structure of your heart’s left ventricle
Valvular heart disease, without symptoms
People in stages C or D of heart failure have an actual heart failure diagnosis.
Stage C involves structural heart disease with prior or current heart failure symptoms.
Stage D is known as refractory heart failure. That means even when you’re at rest and are following your guideline-directed medication therapy, you’re still having heart failure symptoms and might be getting hospitalized over and over again.
Which medications do you take in each stage?
Here’s what heart failure treatment looks like in each of those stages. To find out exactly how each of these medications work, head to this comprehensive post on heart failure medications or check out our short suggested list below.