Tests and diagnosis

By Mayo Clinic Staff

Your doctor may suspect endocarditis based on your medical history and physical signs and symptoms, such as fever. Using a stethoscope to listen to your heart, your doctor may hear a new heart murmur or a change in a previous heart murmur — possible signs of endocarditis.

The infection can mimic other illnesses in its early stages. Various tests may be necessary to help make the diagnosis:

  • Blood tests. The most important test is a blood culture used to identify bacteria in the bloodstream. Blood tests can also help your doctor identify certain conditions, including anemia — a shortage of healthy red blood cells that can be a sign of endocarditis.
  • Transesophageal echocardiogram. An echocardiogram uses sound waves to produce images of your heart at work. This type of echocardiogram allows your doctor to get a closer look at your heart valves. It's often used to check for vegetations or infected tissue. During this test, an ultrasound device is passed through your mouth and into your esophagus — the tube that connects your mouth and stomach.
  • Electrocardiogram (ECG). Your doctor may order this noninvasive test if he or she thinks endocarditis may be causing an irregular heartbeat. During an ECG, sensors (electrodes) that can detect the electrical activity of your heart are attached to your chest and sometimes to your limbs. An ECG measures the timing and duration of each electrical phase in your heartbeat.
  • Chest X-ray. X-ray images help your doctor see the condition of your lungs and heart. Your doctor can use X-ray images to see if endocarditis has caused your heart to enlarge or if infection has spread to your lungs.
  • Computerized tomography (CT) scan or magnetic resonance imaging (MRI). You may need a CT or MRI scan of your brain, chest or other parts of your body if your doctor thinks that infection has spread to these areas.
Aug. 11, 2011