Skip to main content

Causes of heart failure

  • Coronary artery disease

    blocked arteryWhen plaque (fatty deposits) builds up on the inside of your heart's arteries, it reduces the amount of blood and oxygen your heart receives.

    As a result, your heart muscle may become damaged. Your heart becomes weak and less blood gets pumped to the rest of your body.

    Heart attack warning signs

    Call 911 right away if you have:

    • chest pain or pressure
    • pain moving to your arm, neck, jaw, back or abdomen
    • unexplained nausea, heartburn or both
    • shortness of breath

    Heart attack

    When an artery to the heart becomes completely blocked, the part of the heart muscle that receives blood from that artery dies.

    This is called a heart attack (myocardial infarction). It can feel like a crushing type of pain and usually lasts longer than angina (general chest pain).

    A heart attack leaves your heart permanently damaged or scarred. This means the undamaged part of your heart has to work harder.

    High blood pressure

    When the amount of pressure inside your arteries is high, your heart has to pump with more force to push the blood through the blood vessels. If high blood pressure (hypertension) is not treated, your heart muscle becomes larger and its pumping ability weakens.

    High blood pressure usually has no signs. Your blood pressure is checked with two numbers. The top (systolic) shows the pressure in your arteries when your heart beats. The bottom (diastolic) shows the pressure in your arteries when your heart rests.

    You have high blood pressure if you usually have a top number of 130 or higher or a bottom number of 80 or higher.

    diseased valve

    When a valve is diseased, blood can flow in the wrong direction. This causes blood to pool.

    Valve disease

    When one or more of your heart valves no longer opens or closes right, blood can flow in the wrong direction. This is called regurgitation.

    If the opening of the valve is narrow or smaller than usual, your heart has to work harder to pump blood through it. This is called valve stenosis. Your heart becomes thickened or enlarged. It will lose the ability to pump well.

    Idiopathic cardiomyopathy

    When your heart becomes weak and loses its basic ability to pump with force, you will have heart failure symptoms. "Cardiomyopathy" is a term for a weak heart muscle. "Idiopathic" means without a known cause.

    Other causes of heart failure include:


    You may develop high blood pressure during pregnancy. This condition is called preeclampsia. If you had high blood pressure before your pregnancy, the condition may become worse.

    Birth defect

    Part of your heart may not have developed correctly. This is known as congenital heart disease.


    Your valves, heart muscle or both may be damaged by a viral or bacterial infection.

    Lung disease or diabetes

    Both of these diseases put extra strain on your heart. The extra work can cause your heart muscle to weaken.

    Alcohol, illegal drugs, chemotherapy or other toxins

    These can damage the heart muscle.

    Morbid obesity

    Being more than 100 pounds overweight puts more strain on your heart.