Transthoracic echocardiography — standard adult study
Parasternal long and short axis, apical four-, five-, two- and three-chamber, subcostal and suprasternal windows, with two-dimensional, M-mode, colour, spectral and tissue Doppler.
Typical, not policy
Timings, volumes and delays here are representative values drawn from published guidance. Scanner generation, injector, cardiac output and local preference all move them. Confirm against your department's own protocol before you rely on a number.
When to use it
- Suspected heart failure with a raised natriuretic peptide, to measure ejection fraction and identify the mechanism.
- Murmur, suspected valve disease, or surveillance of known valve disease.
- Estimation of pulmonary artery systolic pressure where pulmonary hypertension is suspected — the screening test that precedes right heart catheterisation.
- Pericardial effusion and suspected tamponade.
- Before cardiac MRI in most pathways, because echo answers the question outright in the majority and defines what MRI is being asked to add.
- Suspected endocarditis or cardiac source of embolus, as the first step before transoesophageal study.
Technique
- Pulmonary artery systolic pressure is estimated from the peak tricuspid regurgitant velocity plus an estimate of right atrial pressure from the inferior vena cava — it is a derived number, not a measured one.
- Where endocardial definition is poor, an ultrasound microbubble agent can be given to opacify the left ventricle; that converts the study into a contrast examination with its own consent and access requirements.
- Diastolic function requires a set of measurements together — mitral inflow, tissue Doppler annular velocities, left atrial volume, tricuspid regurgitant velocity — and no single one of them grades it.
Where it goes wrong
- A poor acoustic window in obesity, hyperinflation or ventilation is common and is a real result: it should prompt contrast echo, transoesophageal study or cardiac MRI rather than a repeat of the same examination.
- Absent or trivial tricuspid regurgitation means pulmonary pressure cannot be estimated at all — this is not the same as a normal pressure, and reading it that way misses pulmonary hypertension.
- Ejection fraction is load- and operator-dependent and is not interchangeable between echo and cardiac MRI; serial comparisons should stay within one modality where a threshold decision such as device implantation depends on it.
- A normal echo does not exclude coronary disease.
Clinical questions that reach this study
Contrast
None
Acquisition
- Breathing
- Free breathing, with held expiration for selected Doppler traces.
- Preparation
- State the specific question — function, valve, pulmonary pressures, source of embolus, pericardial effusion — because the sweep and the measurements differ. No fasting or preparation for a standard transthoracic study.