echocardiography

Last edited 12/2022 and last reviewed 02/2023

Echocardiography uses ultrasound to provide a real-time image of the heart. Notably:

• it is non-invasive and is thought to be harmless
• the ultrasound generator and receiver is a piezo- electric crystal
• for high resolution images a high frequency ultrasound must be used - this is 2 MHz for adults and 7 MHz for infants

Notes (1):

• heart failure:
  • in the absence of a significant cardiac history, and with a normal physical examination and 12-lead electrocardiogram (ECG), then the presence of simple cardiomegaly (without pulmonary congestion or other findings suggestive of cardiac disease) on a chest X-ray does not warrant an echocardiogram as the likely yield of identifying significant cardiac pathology is low
• hypertension:
  • an echocardiogram is not indicated routinely to evaluate patients with hypertension, particularly when a normal 12-lead ECG and physical examination is present (1)

Reference:

• Potter A et al. Referring for echocardiography: when not to test. BJGP 2021; 71 (708): 333-334.