To diagnose heart failure, your doctor will carefully review your medical history and symptoms and do a physical exam. Your doctor will also check if you have risk factors for heart failure, such as high blood pressure, coronary artery disease, or diabetes.
Your doctor may listen to your lungs for signs of fluid buildup (pulmonary congestion) and your heart for whistling sounds (murmurs) that may suggest heart failure. The doctor can examine the veins in your neck and check for fluid buildup in your abdomen and legs.
After the physical examination, the doctor may also request any of these tests:
- Blood test. Blood tests are done to look for signs of diseases that can affect the heart.
Chest X-ray. X-ray images can show the condition of the lungs and heart.
- Electrocardiogram. This quick and painless test records the electrical signals of the heart. It can show the time and duration of the heartbeat.
- Echocardiogram. Sound waves are used to produce moving images of the heart. This test shows the size and structure of the heart and the heart valves and the blood flow through the heart. An echocardiogram can be used to measure the ejection fraction, which shows how well the heart is pumping and helps classify heart failure and guide treatment.
- Stress test. Stress tests measure heart health during activity. You may be asked to walk on a treadmill while attached to an EKG machine, or you may receive an IV medication that stimulates the effect of exercise on the heart.
- Sometimes a stress test is done with a mask that measures how well the heart and lungs get oxygen and how they breathe out carbon dioxide.
- CT scan of the heart. In a cardiac CT scan, you lie on a table inside a donut-shaped machine. Inside the machine, an x-ray tube rotates around the body, taking pictures of the heart and chest. Sometimes contrast is provided. Talk to your doctor if you have kidney problems, as the contrast agent could affect kidney function.
- Magnetic resonance imaging. In a cardiac MRI, you lie on a table inside a long tube-shaped machine. Radio waves create images of the heart.
- A cardiac MRI may be done with a dye (contrast). It is important to tell your doctor about any problems with your kidneys before having a cardiac MRI or other MRI because the contrast dye can cause a rare and serious complication in people who have kidney disease.
- coronary angiography. In this test, a thin, flexible tube (catheter) is inserted into a blood vessel, usually in the groin, and guided to the arteries of the heart. A dye (contrast) is injected through the catheter to make the arteries show up more clearly on an x-ray, helping the doctor detect blockages.
- Myocardial biopsy. In this test, a doctor inserts a small flexible cord into a vein in the neck or groin and takes small pieces of heart muscle for analysis. This test may be done to diagnose certain types of heart muscle diseases that lead to heart failure.
The results of tests to diagnose heart failure help doctors determine the cause of any signs and symptoms and decide on a treatment plan. To determine the best treatment for heart failure, doctors can classify heart failure using two systems:
New York Heart Association Classification
This scale groups heart failure into four categories.
- Class I heart failure. There are no symptoms of heart failure.
- Class II heart failure. Daily activities can be done without difficulty, but exertion causes shortness of breath or fatigue.
- Class III heart failure. It is difficult to do daily activities.
- Class IV heart failure. Shortness of breath occurs even while you are at rest. This category includes the most severe heart failure.
American College of Cardiology/American Heart Association Classification
The stage-based classification system uses letters A through D and includes a category for people who are at risk of developing heart failure. Doctors use this classification system to identify risk factors and to start early and more rigorous treatment to help prevent or delay heart failure.
- Stage A. There are various risk factors for heart failure, but there are no signs or symptoms.
- Stage B. Heart disease is present, but there are no signs or symptoms of heart failure.
- Stage C. There is heart disease, signs and symptoms of heart failure.
- Stage D. Advanced heart failure requires specialized treatments.
The physician will often use both classification systems together to decide the most appropriate treatment options. Your doctor can help you interpret your score and plan treatment based on your condition.