The diagnosis of heart failure is made largely on a patient's symptoms and a physical exam. However, there are many tests that can help give more information about the condition.
An echocardiogram (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 doctor 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 versus 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 around 55 - 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.
Other imaging tests
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 doctor'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 of the heart may be done to check how much heart muscle damage is present. It can also help detect 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
Your doctor may order a heart catheterization if any imaging tests show that you have narrowing in one of your arteries, or if you are having chest pain (angina).
Many different blood tests can be used to learn more about your condition, including tests to:
Help diagnose 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 medications you may be taking
Blood urea nitrogen (BUN) and serum creatinine tests help monitor how well your kidneys are working. You will need these test regularly if:
You are taking medicines called ACE inhibitors or ARBs (angiotensin receptor blockers)
Your doctor 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) 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. So your doctor will check your CBC or complete blood count on a regular basis or when your symptoms become worse.
Yancy CW, et al. 2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. Published online June 5, 2013.
Mann DL. Management of heart failure patients with reduced ejection fraction. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 28.
Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.