Causes of heart failure

According to the Centers for Disease Control and Prevention, nearly 6.5 million adults in the United States have heart failure. Heart failure (HF) is a condition in which the heart has trouble pumping blood. This is because the heart has become weak or stiff due to specific health problems or lifestyles. When your heart is not pumping blood normally, it is hard for your body to work well because it is not getting enough blood and oxygen. 

Heart failure is usually a lifelong condition. If you are diagnosed with heart failure, it is important to follow a treatment plan from your healthcare providers and to take good care of your health.

The heart has four chambers. All four chambers need to function normally for the body to get enough blood and oxygen. The right atrium and left atrium are the two upper chambers of the heart. The right ventricle and left ventricle are the two lower chambers. Blood that comes from the body enters the heart through the right atrium and then flows into the right ventricle. The same blood then flows to the lungs from the right ventricle. This is where the blood picks up oxygen. The blood carrying oxygen comes back to the heart through the left atrium and into the left ventricle. The blood is then pumped out to the entire body.

There are different types of heart failure, based on which functions of the heart are affected.

Heart failure is also sometimes referred to as congestive heart failure (CHF). CHF is a stage of heart failure in which fluid builds up around the heart causing difficulty for the heart to pump blood. The different types of heart failure are defined by ejection fraction, which is how well the heart is able to pump.

Left-sided heart failure (two types):

• In heart failure with reduced ejection fraction, also called HFrEF or systolic heart failure, the heart is too weak and can’t pump or squeeze enough blood out to the rest of the body. 
• In heart failure with preserved ejection fraction, also called HFpEF or diastolic heart failure, the heart is too stiff and can’t fill with enough blood when the heart tries to relax.

Congenital heart disease can lead to heart failure and is usually present at birth due to a heart defect during development or inherited heart disease.

High-output heart failure is an uncommon type of heart failure where the body requires unusually high amounts of blood due to other conditions, such as obesity, liver disease, severe infections or overactive thyroid.

Acute decompensated heart failure (ADHF) is the sudden onset of new or worsening heart failure signs and symptoms. ADHF is a medical emergency and requires immediate care.

Heart failure can be managed by lifestyle changes or medications prescribed by your healthcare providers to help treat symptoms. There are different medication classes, and each class has a different way of treating HFrEF or HFpEF. You may need multiple medications to help manage heart failure symptoms.

These include angiotensin-converting enzyme inhibitor (ACE inhibitor), angiotensin II receptor blocker (ARB) or angiotensin receptor-neprilysin inhibitor (ARNI). They work similarly by dilating (widening) blood vessels, lowering blood pressure and increasing the supply of oxygen and blood to the heart. Your healthcare providers will usually only choose one medication from one of these three classes of medications.

Beta-blockers allow the heart to relax and work less by lowering your blood pressure.

Diuretics, also called “water pills,” help your kidneys produce more urine to remove excess salt and water from your body. Reducing the extra fluid that can build up in heart failure makes it easier for your heart to pump blood to the rest of your body and also lowers blood pressure.

Other medications may be needed to control symptoms in addition to the medications above, and include aldosterone antagonist or mineralocorticoid receptor antagonist, which is a type of diuretic that helps your kidneys produce more urine to remove excess salt and water from your body. Reducing fluid that builds up in heart failure makes it easier for your heart to pump blood to the rest of your body and also lowers blood pressure. 

Nitrate and hydralazine can be combined into one pill called BiDil or prescribed separately. Hydralazine helps relax and widen veins and arteries, making it easier for your heart to pump. Isosorbide dinitrate is a nitrate that helps widen blood vessels. This makes it easier for blood to flow and for the heart to pump.

Digoxin helps your heart pump better and can control or slow your heart rate. It is used to improve the strength and efficiency of the heart.

The most commonly prescribed medications in these classes include (brand name in parenthesis):

If you’ve been diagnosed with heart failure, there are several steps you can take to manage the condition:

• Know the signs and symptoms of heart failure 
• Lifestyle changes include weight loss,  quitting smoking or chewing tobacco, eating heart-healthy foods, avoiding alcohol and illicit drug use, and increasing physical activity
• Limit salt and fluid intake as directed by your healthcare provider
• Follow your Heart Failure Action Plan, and take all medications as prescribed