Critical care echocardiography (CCE) is a well-established method to evaluate and monitor patients with hemodynamic failure. Use of CCE is a routine part of critical care practice coincident with its introduction into training programs and the widespread availability of courses for attending level intensivists who seek competence in the field [1–3]. We have identified a number of false perceptions regarding CCE (Fig. 1). The editor of Intensive Care Medicine has asked us to review ten of these false myths, the discussion of which is the subject of this editorial.

Fig. 1
figure 1

The ten positive, negative and “neutral” issues regarding critical care echocardiography (CCE). TEE transesophageal echocardiography

Full size image

  • Myth #1 Every CCE examination should be comprehensive.

  • No, this is not the case.

The CCE examination is tailored to the clinical situation. Basic CCE utilizes a limited number of views to rule out an imminently life-threatening process, to categorize shock state, and to guide management. This approach, when combined with other elements of critical care ultrasonography, is effective in establishing diagnosis and helpful in guiding treatment [4].

The intensivist with competence in advanced CCE has skill level near similar to the cardiologist with some exceptions such as detailed assessment of artificial valves, analysis of complex congenital disease, decisions related to mitral valve repair, or use of advanced techniques such as 3-D imaging or strain rate. The intensivist may perform a complete examination if required, but also performs serial limited examinations that are pertinent to the clinical situation.

  • Myth #2 CCE is not a monitoring tool.

  • Yes, it is.

The routine use of serial examinations to track the evolution of critical illness, the response to therapeutic intervention, and to search for new or confounding diagnoses is integral to CCE. Serial monitoring examinations are a defining element of CCE. This may include a complex quantitative analysis of cardiac pressures and flows using a full array of Doppler technique or be simple qualitative visual estimates of cardiac function. While standard CCE does not provide continuous hemodynamic monitoring, it is effective for intermittent monitoring of hemodynamic function. Depending on the clinical situation and the local capability to perform echocardiography, CCE can be used alone or in association with other hemodynamic monitoring methods.

  • Myth #3 Intensivists do not need cardiologists.

  • Yes, they do.

The intensivist with skill at basic CCE has limited capability in echocardiography, so the basic examination will often be followed by a comprehensive examination that requires a fully trained cardiology echocardiographer or an intensivist who is competent in advanced CCE.

The intensivist with skill at advanced CCE recognizes that there are parts of echocardiography that are not within their purview, such as detailed assessment of artificial valves, complex congenital disease, or decisions related to mitral valve repair. In this situation, the intensivist always partners with the cardiologist. Conversely, the intensivist has skill at aspects of advanced CCE that are not within the classical scope of practice of the cardiologist such as heart–lung interactions during ventilator use or serial estimates of stroke volume and left atrial pressure in response to therapy. The effective use of CCE requires a cooperative relationship between the cardiologist and intensivist.

  • Myth #4 CCE is less reliable than other hemodynamic tools.

  • No, it is not.

For example, cardiac output is a measurement common to many invasive hemodynamic tools. It can be computed by CCE using Doppler-based methods as an alternative to thermodilution [5] without the risk of an invasive vascular device. Major therapeutic interventions such as fluid boluses or periods of significant hemodynamic instability may result in unacceptable inaccuracies in cardiac output measurement by some continuous invasive methods [6–8].

  • Myth #5 In refractory or complicated shock, CCE should be replaced by an alternative invasive device.

  • No, this is not the case.

In this setting, CCE is the best available tool that is capable of independently assessing causes for cardiovascular instability such as detection of fluid responsiveness, characterization of systolic and diastolic function, assessment of preload/afterload of both ventricles, and categorization of complicated shock. The assessment of RV function and interventricular dependence by CCE also allows specific adjustments of the ventilator in patients with shock and ARDS [9].

  • Myth #6 Training in transesophageal echocardiography (TEE) is an optional part of advanced CCE training.

  • No, it is not.

Training in TEE is an essential part of advanced CCE training [2, 3]. A primary indication for TEE is when transthoracic echocardiography (TTE) is of poor quality due to patient-specific factors. Use of TEE is easy and safe in sedated patients under mechanical ventilation, even in the prone position [10]. Compared to TTE, TEE is less dependent on operator skill, has better spatial resolution, and is superior for assessment of great vessels, heart valves, endocarditis [11], intracardiac shunt, and cor pulmonale [12]. These diagnoses have important clinical implications [13, 14].

  • Myth #7 It is easy to achieve competence in CCE.

  • No, it is not.

This is a dangerous myth, as it risks that the intensivists will not develop the necessary competence yet consider that they have mastery of CCE. This will impact adversely on patient outcome, and bring discredit to the field. We caution that mastery of CCE may appear to be straightforward. This is not the case, so faculty have special responsibility to provide adequate training. This requires design of comprehensive training for residents and fellows, as well as the development of effective courses for attending level clinicians [1–3]. We all have a responsibility be truly competent in CCE, as this is a key element for widespread acceptance of CCE. This is with the understanding that it is easier obtain skill in basic level compared to advanced CCE.

  • Myths #8 and 9 There is a strong evidence base that supports CCE, and CCE is academically supported worldwide.

  • No, unfortunately, this is not the case.

Front-line intensivists have adopted CCE based upon it intuitively obvious utility. This has occurred despite the relative lack of evidence-based literature. For example, there is no study that shows that CCE alters mortality of critical illness. It will be difficult to design studies on mortality given the challenges to study design, and the lack of clinical equipoise by clinicians who use CCE. The most direct effect on mortality might be observed by studying imminently life-threatening processes such as pericardial tamponade or massive pulmonary embolism. It is difficult to envision a randomized controlled trial of the CCE for these entities. Still, we encourage any attempt to measure its effect on mortality.

The development of academic support for CCE is limited by the fact that most of the recently published new approaches based on CCE to optimize hemodynamics or ventilator settings have been published by a small circle of researchers who are strong believers in CCE and come from only a few countries. This represents a challenge to the external validity of their work. Most of these published studies are based on a pathophysiological research approach or are observational, so they do not conform to evidence-based study design. The field needs studies that examine the effect of CCE on important clinical outcomes. The lack of academic support may be remedied by developing international collaborative studies and by creating an international certification process available to all intensivists.

  • Myth #10 There is no risk of medico-legal issues.

  • Yes, there is.

Misinterpretation of CCE results may lead to misdiagnosis or inaccurate monitoring results, the consequence being poor patient outcome. This is a medico-legal risk common to all imaging and monitoring methods in the intensive care unit, and is not unique to CCE. To reduce this type of risk, intensivists need to have adequate training with resulting competence, so that they can use CCE in a safe and effective manner. Conversely, as CCE becomes more widespread, it is inevitable that it will be regarded as a required competence. If a lack competence results in a poor patient outcome when the intensivist should have had the requisite skill but did not, the intensivist may face medico-legal risk. This has already happened in the case of ultrasonography guided vascular access, where intensivists who choose not to use this modality expose themselves to medico-legal risk. The same may soon be the case for CCE.