The versatility of transthoracic echo (TTE) means that it can play a useful role in a diverse range of clinical situations. The British Society of Echocardiography (BSE) has published guidance on the appropriate clinical indications for TTE (see Further Reading). The American College of Cardiology Foundation has also produced guidance (jointly with a number of other societies). The two sets of guidelines are broadly similar and describe echo as being an appropriate investigation in the assessment of patients with:

Transthoracic echo is also indicated for pre-operative assessment in patients awaiting elective or semi-urgent surgery if they have:

It is essential that echo requests contain adequate clinical data both to judge the appropriateness of the request and also to allow the sonographer to place the echo findings into an appropriate clinical context (see the box ‘Sensitivity, specificity and Bayesian analysis’). Echo requests must therefore carry appropriate clinical details and contain information about known cardiac diagnoses or previous cardiac interventions/surgery (e.g. prosthetic valves). Clinicians requesting echo studies should be encouraged to include specific questions with their request (e.g. ‘Does this patient have pulmonary hypertension?’), as this provides a clear focus for the echo study and ensures that the sonographer can address the specific concerns of the clinician.

Patients attending for an echo study may feel anxious, not only about having the test itself but also about any abnormalities that it may reveal. To help reduce anxiety, describe the test to patients in clear and reassuring terms – explain to patients why they are having an echo, whether any special preparation is needed before they attend, what happens during the scan and how long it is likely to take. Reassure patients that having an echo is safe and painless. Patients can eat and drink normally before attending for a standard TTE, and they can take their medication as usual.

It is good practice to offer patients an information leaflet before they attend (and to make available large-print/Braille and translated versions as appropriate). The patient information leaflet and/or appointment letter can also invite the patient to bring a friend or relative if they wish to have someone accompany them during the echo. If a friend or relative does not accompany the patient when they attend, offer the patient a chaperone in line with hospital policy.

Prior to performing the echo study, it is good practice to record the patient’s height and weight, as this will allow the indexing of echo measurements for body surface area. You should also ideally record the patient’s heart rate and blood pressure.

Once you have checked that the patient understands the test that is about to be performed, ask the patient to undress to the waist for the echo study. Always offer female patients a gown to wear during the echo (even if the sonographer is female). Ask the patient to sit on the echo couch and recline at 45°, rolling on to their left side. The patient should then raise their left arm and place their left hand behind their head. Be sure to check if the patient has any physical limitations that may make it difficult or uncomfortable for them to adopt this position. If so, you may need to adapt the patient’s position until they are comfortable. Sonographers who prefer to scan left-handed will also need to adapt the patient’s positioning accordingly.

When the patient is in a comfortable position, apply the ECG electrodes and ensure that a clear ECG tracing is visible on the screen of the echo machine. You may need to adjust the electrodes and/or the ECG gain setting to obtain a good trace. Ensure that the correct patient identification and clinical details are entered into the echo machine, and then perform and report the study as described in the sections that follow. At the end of the study, explain to the patient that you will be writing a report which will be sent to the referring clinician. Patients may ask you what the study has shown, but you should not discuss the study findings at this stage and it is usually better to redirect persistent requests for information to the referring clinician.

The BSE has produced a guidance document, entitled A Standard Transthoracic Echocardiogram, which provides a framework for performing a comprehensive transthoracic echo study. This document forms the basis of the approach outlined in this chapter, and identifies minimum requirements and recommendations (in terms of views and measurements).

A comprehensive echo study should include not only the minimum requirements but also the recommendations, and this is particularly important in individuals who are being scanned for the first time. Moreover, if pathology is found, then additional views/measurements (over and above the minimum requirements and recommendations) may be appropriate. However, it is also acknowledged that some echo studies (for instance follow-up studies, or focussed/targeted studies) will not necessarily need to include all of the minimum requirements described here.

There are five TTE windows (Fig. 6.1), each providing one or more views of the heart. The right parasternal window is optional and can be used when other views are suboptimal or when additional information is needed: