Back to top

Ultrasound - Basic cardiac

Indications

To assess and exclude the presence of three specific pathologies:

Pericardial effusion

Right heart failure

Left ventricular dysfunction (global)

Consider in the following presentations:

Cardiac arrest

Unexplained hypotension

Dyspnoea

Chest pain

Syncope

Trauma

Contraindications (absolute in bold)

Airway management or resuscitation required

Alternatives

Nil

Informed consent

Medical emergency

Consent is not required if the patient lacks capacity or is unable to consent

Brief verbal discussion is recommended if the situation allows

or

Verbal consent

Less complex non-emergency procedure with low risk of complications

Potential complications

Failure to obtain adequate views (bone or air artefact, excess tissue)

Failure of image interpretation (false negative or positive)

Procedural hygiene

Standard precautions

PPE: non-sterile gloves

Area

Any bed

Staff

Procedural clinician

Equipment

Towel

Ultrasound machine and gel

Phased array ultrasound probe (orientation described below)

Curvilinear ultrasound probe (may be used for subcostal window)

Positioning (marker descriptions for phased array cardiac probe)

Supine for subcostal view

Left lateral position with arm above head for parasternal and apical view

Subcostal: probe inferior to xiphoid directed towards patient’s left shoulder (marker to the left)

Parasternal long axis: probe at left sternal edge between second and fifth intercostal space (marker to right clavicle)

Parasternal short axis: rotate probe 90 degrees clockwise from long axis view (marker to left shoulder)

Apical four chamber: positioned at maximum apical beat or fifth intercostal space anterior axillary line (marker left)

Sequence (scanning)

Subcostal: apply firm downward pressure, angling the probe slowly up from the abdomen into the left chest

Parasternal long axis: drag probe over the chest wall between second and fifth intercostal space searching for the best window

Parasternal short axis: tilt the probe sweeping through the heart from base to apex obtain views at all levels

Apical four chamber: direct towards the patient’s head, dragging probe over chest searching for the best window

Sequence (left ventricular function assessment)

Visualise LV function (myocardial thickening and endocardial excursion) in multiple views

Gross visual assessment only (measurements are not required in the basic cardiac echo)

Define LV function: hyperdynamic, normal, moderately depressed, severely depressed or standstill

Sequence (pericardial effusion assessment)

Visualise the pericardium and any pericardial fluid in multiple views

Estimate the greatest depth of pericardial effusion (measurements are not required in the basic cardiac echo)

Define pericardial effusion: none, small (<0.5cm), moderate (0.5-2.0cm), large (>2cm)

Sequence (right heart dilation)

Visualise LV and RV diameter in multiple view (the usual RV:LV ratio is 0.6:1)

Define RV dilation: none (RV smaller than LV), moderate or more (RV larger than LV)

Post-procedure care

Clean ultrasound gel from patient

Document estimated LV function, presence of pericardial fluid and right ventricular dilation

Complete clinical assessment combining results with clinical history, exam and other investigations

Tips

It is not always possible to obtain all four cardiac views on every patient

The subcostal view is sometimes the only view we can get during resuscitation or CPR

Attempt to obtain all views, however one or more views may answer all three questions of basic echo

Echo all hypotensive patients, and assimilate your finding with the rest of your assessment

Discussion

By convention the probe marker is on the opposite side of the probe for both the phased array ultrasound probe (cardiac) and the curvilinear ultrasound probe (abdominal). This is relevant for emergency department ultrasound where we use machines incorporating both a phased array ultrasound probe (cardiac) and a curvilinear ultrasound probe (abdominal).

This text describes probe orientation for the phased array cardiac probe. When the curvilinear abdominal probe is used (e.g. in the subxiphoid window) the marker needs to be pointed in the opposite direction (right) to obtain the same view.

When evaluating cardiac motion during CPR, terminal cardiac dysfunction typically progresses through global ventricular hypokinesis, incomplete systolic valve closure, absence of valve motion, absence of ventricular motion, and finally culminating in intracardiac gel-like densities. A lack of mechanical cardiac activity seen on bedside echo has a very poor prognosis, and can assist the decision to terminate resuscitation.

Published investigations demonstrate that emergency physicians with relatively limited training and experience can accurately estimate global cardiac ejection fraction. Left ventricular systolic function is typically graded as normal (EF>50%), moderately depressed (EF 30-50%), or severely depressed (EF<30%).

Peer review

This guideline has been reviewed and approved by the following expert groups:

Emergency Care Institute

Please direct feedback for this procedure to ACI-ECIs@health.nsw.gov.au.

References

Roberts JR, Custalow CB, Thomsen TW. Roberts and Hedges’ clinical procedures in emergency medicine and acute care. 7th ed. Philadelphia, PA: Elsevier; 2019.

Dunn RJ, Borland M, O’Brien D (eds.). The emergency medicine manual. Online ed. Tennyson, SA: Venom Publishing; 2019.

Manoj P, et al (2019): In: UpToDate. Waltham (MA): UpToDate.: Emergency ultrasound in adults with abdominal and thoracic trauma

Emergency ultrasound imaging criteria compendium. Ann Emerg Med. 2016;68(1):e11-e48. doi:10.1016/j.annemergmed.2016.04.028

Dawson M, Mallin M. Introduction to bedside ultrasound: volume 1. New York NY: Apple Books; 2013.

Dawson M, Mallin M. Introduction to bedside ultrasound: volume 2. New York NY: Apple Books; 2013.

© Agency for Clinical Innovation 2021