An echocardiogram (cardiac echo) is a test that uses sound waves to create a moving picture of the heart. The picture is much more detailed than a plain x-ray image.

This test helps your health care provider learn more about how well your heart contracts and relaxes. It also provides information about the size of your heart and how well the heart valves are working.

An echocardiogram is the best test to:

• Identify which type of heart failure (systolic, diastolic, valvular)
• Monitor your heart failure and guide your treatment

Heart failure can be diagnosed if the echocardiogram shows that the pumping function of the heart is too low. This is called an ejection fraction. A normal ejection fraction is 55% to 65%.

If only some parts of the heart are not working correctly, it may mean that there is a blockage in the artery of the heart that delivers blood to that area.

Many other imaging tests are used to look at how well your heart is able to pump blood and the extent of heart muscle damage.

You may have a chest x-ray done in your provider's office if your symptoms suddenly become worse. However, a chest x-ray cannot diagnose heart failure.

Ventriculography is another test that measures the overall squeezing strength of the heart (ejection fraction). Like an echocardiogram, it can show parts of the heart muscle that are not moving well. This test uses x-ray contrast fluid to fill the pumping chamber of the heart and evaluate its function. It is often done at the same time as other tests, such as coronary angiography.

MRI, CT, or PET scans of the heart may be done to check how much heart muscle damage is present. It can also help determine the reason for a patient's heart failure.

Stress tests are done to see whether the heart muscle is getting enough blood flow and oxygen when it is working hard (under stress). Types of stress tests include:

• Nuclear stress test
• Exercise stress test
• Stress echocardiogram

Your provider may order a heart catheterization if any imaging tests suggest that you have narrowing in one of your arteries, or if you are having chest pain (angina) or a more definitive test is desired.

Several different blood tests can be used to learn more about your condition. Tests are done to:

• Help diagnose the cause for and monitor heart failure.
• Identify risk factors for heart disease.
• Look for possible causes of heart failure or problems that may make your heart failure worse.
• Monitor side effects of medicines you may be taking.

Blood urea nitrogen (BUN) and serum creatinine tests help monitor how well your kidneys are working. You will need these tests regularly if:

• You are taking medicines called ACE inhibitors or ARBs (angiotensin receptor blockers)
• Your provider makes changes to the doses of your medicines
• You have more severe heart failure

Sodium and potassium levels in your blood will need to be measured on a regular basis when there are changes made for some medicines including:

• ACE inhibitors, ARBs, or certain types of water pills (amiloride, spironolactone, and triamterene) and other medicines that can make your potassium levels too high
• Most other types of water pills, which can make your sodium too low or your potassium too high

Anemia, or low red blood cell count, can make your heart failure worse. Your provider will check your CBC or complete blood count on a regular basis or when your symptoms become worse.

CHF - tests; Congestive heart failure - tests; Cardiomyopathy - tests; HF - tests

Greenberg B, Kim PJ, Kahn AM. Clinical evaluation of heart failure. In: Felker GM, Mann DL, eds. Heart Failure: A Companion to Braunwald's Heart Disease. 4th ed. Philadelphia, PA: Elsevier, 2020:chap 31.

Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure: a report of the American College of Cardiology/American Heart Association Joint Committee on clinical practice guidelines. J Am Coll Cardiol. 2023;81(15):1551. PMID: 35379503 pubmed.ncbi.nlm.nih.gov/35379503/.

Mann DL. Management of heart failure patients with reduced ejection fraction. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 50.

Updated by: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.