What Is a Standard Transthoracic Echocardiogram Performed by a Cardiologist?

Introduction

The first “Guidelines for quality maintenance in echocardiography” were published by the Working Group of Echocardiography of the Swiss Society of Cardiology in 1999, then revised in 2009 [1].

The Board of the Swiss Society of Cardiology, pursuing a new quality strategy, mandated the Working Group of Echocardiography and Cardiac Imaging to redefine the standards of an adult trans-thoracic echocardiographic examination performed by a cardiologist. The transthoracic echocardiographic examination performed by a cardiologist is not only expected to be of high technical quality and accuracy (through education and training), but also complete. Therefore, image acquisition and analysis as well as the final report have to be strictly standardised. Moreover, quantitative Echocardiography should be the rule when feasible and will include extra time for measurements and post-processing, which has to be taken into account in the clinical workflow of an echolab. The echocardiographic examination has to be performed according to the guidelines of the European Society of Cardiology mentioned at the end of this document 2–12 and available on the site of the Working Group (swissecho.ch/Documents).

Solid knowledge of cardiac anatomy, physiology and pathophysiology is a pre-requisite for correct interpretation of a transthoracic echocardiogram.

In this document, the WG will specify in detail: (1.) the image acquisition protocol; (2.) the post-processing of the images, including quantitative or semiquantitative analysis and measurements; (3.) contents of a comprehensive and structured report of a standard transthoracic echocardiographic examination performed by a cardiologist for all subjects being scanned. Recommendations reported in this document represent the standard requirements of a routine examination. Detection of specific abnormalities may need supplementary dedicated views and analyses.

A conclusion will finalise this report, highlighting the abnormal findings in a hierarchic way and establishing the final diagnosis by an integration of imaging and clinical data. This integration is the reason why the WG still strongly has the opinion that a diagnostic transthoracic echocardiographic examination should be performed exclusively by cardiologists based on their expertise in cardiac physiology and diseases.

Indications

The indication for echocardiography has to comply with the appropriateness criteria published in the literature [2].

Equipment

All cardiologists should use an echocardiography machine offering 2D imaging including second harmonic, M-mode, continuous wave/pulsed wave and colour Doppler/tissue Doppler and an optimal ECG gating system. The use of speckle tracking imaging and 3D imaging is encouraged because both can provide additional and more accurate information. A storage system for the cine-loops and still frames is mandatory for archiving. Digitised archiving in dicom format is the preferred standard.

Image acquisition

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First ensure that the ECG tracing is optimal.

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Blood pressure needs to be obtained at the time of the exam, as it is important for the interpretation of findings.

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Before recording, optimise the quality of your images for each view and modality (sector width and depth, frame rate, frequency of the probe, gain settings).

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In case of any abnormality, additional views in zoom mode (with and without colour) have to be acquired.

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For Doppler, alignment of the ultrasound beam with the structure / flow of interest should be optimised (maximal 15 degree angle).

The following tables list the views that should be acquired for a complete transthoracic echocardiography. It should be noted that not in every patient, every view is indispensable and the extent to which this list is followed remains at the discretion of the examining cardiologist. However, it is the opinion of the board that the vast majority of the following views should be acquired in most patients. More acquisitions may be indicated in case of specific findings.

Table 1. Parasternal views.

* The interventricular septum should be perpendicular to the beam for optimal axial resolution and linear measurement.

Table 1. Parasternal views.

* The interventricular septum should be perpendicular to the beam for optimal axial resolution and linear measurement.

Table 2. Apical views*.

* Maintain the same sector depth for the 3 apical views. TDI = tissue Doppler imaging; PISA = proximal iso-velocity surface area.

Table 2. Apical views*.

* Maintain the same sector depth for the 3 apical views. TDI = tissue Doppler imaging; PISA = proximal iso-velocity surface area.

Table 3. Subcostal and suprasternal views.

Table 3. Subcostal and suprasternal views.

Speckle tracking (optional)

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Optimal frame rate is >60 Hz (adjustment of sector width and depth in order to increase frame rate may be necessary)

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Image acquisition in respiratory hold in order to reduce translational motion of the heart during the respiratory cycle

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Acquisition of 3 cycles

Record the LV in 4C, 2C and 3C apical view by 2D / 3D Record the RV in modified 4C view

Measurements

All measurements should be carried out according to ESC/ASE recommendations.

Table 4. Measurements.

Table 4. Measurements.

Table 5. Items that should be included in a standard transthoracic echocardiogram report.

Table 5. Items that should be included in a standard transthoracic echocardiogram report.

Report

The following baseline parameters should figure in the report:

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First and last name

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Age and gender

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Weight, height, body surface area and body mass index

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Blood pressure

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Heart rate and rhythm

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Type of machine (optional)

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Contrast injected; type and dose

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Global image quality of the examination

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Indication for the study

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Past cardiac history including previous cardiac surgery.

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Types of any device or prosthetic valve implanted should be mentioned.

In case the patient has been examined in an intensive care unit, mention the respiratory status (intubated, free breathing, non-invasive ventilation) as well as the therapy (e.g., inotropes) with the dosage and/or other mechanical cardiac support.

Each the items in Table 4 should either be described or mentioned as not correctly visualised. Whenever possible, try to classify findings as: normal – mildly abnormal – moderately abnormal – severely abnormal – not visualised.

Conclusions

Treatment strategies depend upon precise diagnostic evaluation. Echocardiography is one of the most effective diagnostic tools when the data are correctly acquired and reported. A standard adult transthoracic echocardiographic examination performed by a cardiologist is a mixture of technical skill, rigorous approach as well as perfect understanding of cardiac anatomy and physiopathology, which necessitates a dedicated long learning period in experienced centres.

Because ultrasound is a very efficient tool for the non-invasive diagnosis and is free of side effects, other specialists (intensive care and emergency care physicians) are increasingly using this technique for specific needs. While we acknowledge that there is a value for focused cardiac ultrasound in patients in emergency care/intensive care units, we would like to stress that focused cardiac ultrasound does NOT replace an echocardiography performed by a cardiologist, and that in most cases a focused cardiac ultrasound should be followed by a comprehensive quantitative diagnostic echocardiogram performed by a cardiologist.

As regard with the running quality programme, the WG of Echocardiography SSC/SSK will maintain high standards for the transthoracic echocardiographic examination and will make efforts to let every cardiologist acquire and maintain optimal skill in the field of cardiac echocardiography.