Pocket-sized: Pointers for Using (& Not Using) Handheld Point-of-Care Echocardiography
Point-of-care (POC) echocardiography using newer handheld devices is garnering recognition as a valuable clinical assessment modality in emergency departments as well as in non-emergent care. Both cardiologists and emergency physicians told CVB that handhelds are useful inside and outside of the emergency room but voiced concerns and caveats about how and when the devices should be used—and who should be operating them. There also are divergent schools of thought regarding how handheld echocardiography will impact cardiology service lines and the costs of care.
“POC echocardiography is a disruptor—in a good way,” says Amer Johri, MD, associate professor in the department of medicine at Queen’s University and founder and director of the Cardiovascular Imaging Network at Queen’s (CINQ) in Kingston, Ontario. “It has assumed a key role in providing high-caliber patient care.”
Supplement, not substitute
It’s tempting to think that handheld echo devices could stand in for traditional echocardiography equipment, but the truth is they’re a valuable supplement, not a star player, Johri and other sources warn.
“To think otherwise is unrealistic and possibly dangerous,” Johri says. “POC echocardiography [using handhelds] is not for diagnosis, which of course involves formal and specific, well-established cardiovascular protocols. However, it is very viable for binary decision-making, to determine whether and how urgently further testing is needed.”
Jeffrey Geske, MD, a cardiologist at the Mayo Clinic in Rochester, Minn., and a member of the American College of Cardiology’s imaging council, uses handheld echo to answer focused clinical questions, such as whether an inferior vena cava is dilated or normal, an ejection fraction has been substantially reduced or a larger than initially suspected pericardial effusion is present. The device also plays a role in supplementing examinations, for instance, in 2D color flow Doppler correlation when a murmur is auscultated, for visual assessment of left ventricular size when the point of maximal impulse is displaced and in evaluating for pericardial effusion when a pericardial rub was heard, Geske says.
“It’s important to recognize current device limitations compared to standard echocardiography,” he adds, noting, as did some other sources, that this is one reason handhelds should not be used for diagnostic purposes. Many aspects of quantitative echocardiography are not available on handheld devices, he explains, so comparison to prior evaluations can be challenging. Reduced image quality may result in repeat examinations.
In 2013, not long after the handheld devices hit the market, the American Society of Echocardiography (ASE) issued a consensus statement recommending that handhelds can serve as a “useful adjunct” to other methods for bedside evaluation of patients, particularly when standard echocardiography is not available, for instance, in the emergency department (J Am Soc Echocardiogr 2013;26[6]:567-81).
The value of handheld echocardiography in the emergency department has been underscored in studies. For example, one study of 104 patients showed “excellent agreement” between handheld and traditional echo for assessment of left ventricular systolic function and pericardial effusion (Kappa:0.89 and 0.81, respectively). Agreement in evaluating aortic, mitral and tricuspid valve function and left ventricular size proved “good” or “moderate” (Eur Heart J Cardiovasc Imaging 2013;14[1]:38-42).
Emergency departments also favor access to handheld POC echo for answers to focused questions, though not for diagnosis, reports Seth Trueger, MD, MPH, an emergency physician at Northwestern University Hospital in Chicago. “In addition to helping with patient assessment by allowing us to find out, for example, that a patient has pericardial effusion, the availability of POC echocardiography facilitates sorting of patients by required urgency and type of care,” he explains.
A similar adjunctive role may apply outside the emergency department. A study designed to evaluate the use of POC ultrasound examination in the outpatient setting concluded that “a quick-look sign for left atrial enlargement is associated with five-year mortality” and could function as an easily obtained outpatient POC ultrasound examination to help in identifying patients in need of echocardiography referral (Am J Med 2019;132[2]:227-33).
The role of handheld echocardiography devices may expand over time, says Jim Kirkpatrick, MD, adjunct professor of medicine, cardiology and bioethics at the University of Washington School of Medicine. He predicts that increased use of POC echocardiography for decision making eventually will lead to more appropriate use of full-feature machines operated by trained sonographers. “Working in concert, there is the potential to use different levels of ultrasound technology and expertise to improve the rapidity and accuracy of diagnosis,” says Kirkpatrick, who also serves as section chief of cardiovascular imaging, director of echocardiography and chair of the ethics committee at UW Medical Center.
Costs & other questions
Handheld POC echocardiography could impact cardiac service line operations, potentially affecting workflows, reimbursements and costs as well as how cardiologists collaborate with their emergency department colleagues. Whether these changes will be positive or negative sometimes lies in the eye of the beholder. For example, some see handhelds as a useful tool for improving and expediting triage in the emergency department. By weeding out patients who do not require traditional echocardiography, handheld devices could bolster service line efficiencies, some sources say.
Others perceive things differently. “For each time I can think of an example where POC cardiac ultrasound sufficiently answered a goal-directed question and avoided a more comprehensive examination, I can think of at least one example whereby examination [using a handheld POC ultrasound device] raised additional questions,” creating more work for cardiac clinicians, Geske says. “That’s a zero-sum game.”
On the plus side of the cost equation, POC echocardiography can be performed with handheld equipment at what sources deem a fraction of the price of traditional echo. Significant cost savings also can be achieved in cases where POC echocardiography confirms that a more expensive follow-up with standard echo is unnecessary. Others say POC echocardiography is just as likely to point the way to more tests and their associated costs.
Echocardiography labs also can lose reimbursement revenue when POC devices are substituted for standard echo. In such a scenario, fewer traditional echocardiography studies may be ordered and reduced reimbursements may ensue, sources say.
Michael Cullen, MD, a cardiologist at Mayo Clinic Health System in Owatonna, Minn., points out ways to mitigate this particular sting. Topping the list is ensuring, via consistent communication from the cardiac community to other service lines, that all users understand that POC devices “do not substitute for standard echocardiography,” says Cullen, who also practices cardiology and echocardiography at the Mayo Clinic in Rochester, Minn. Making standard echocardiography readily available to off-hours staff around the clock also ranks high. This, Cullen explains, not only provides the best diagnostic testing for patients but also strengthens cardiology’s relationships with the emergency department and other referring clinicians.
Challenges & concerns
While sources told CVB that POC echocardiography’s benefits will ensure it’s here to stay, challenges—albeit not insurmountable ones—have persisted. Training, for example, isn’t a one-size-fits-all proposition.
Training should vary according to the purposes and complexity of individual devices, Kirkpatrick says. “These small devices could be used only to give an estimate of filling pressures or to determine whether there is fluid around the heart but also can be used to discern the function of the right-sided pumping chamber,” he says. The latter task “is much more difficult to [perform] because it is so easy to get the image plane wrong and make the chamber look bigger or smaller than it really is, with better or worse function than it actually has. The reality is that the devices come in multiple shapes and sizes and different levels of functionality,” thus requiring different levels of training and customization to suit particular applications.
Just as significantly, Johri observes, the effectiveness and reliability of handheld POC echocardiography equipment currently depends on the operator and, to a lesser extent, the functionality of the equipment. Erroneous diagnoses or conclusions are among the troubles that can result when the technology is used by operators who lack significant experience with handheld ultrasound units, are unable to interpret the images or both.
According to Kirkpatrick, untrained or underskilled users may conclude that a patient is “fine” when their condition actually needs treatment. Conversely, he says, they may come to conclusions that set off unwarranted “alarm bells,” possibly leading to unnecessary interventions.
“I hope we never see billboards advertising law firms seeking to represent patients who were ‘harmed’ by missed or improper diagnoses made with these small machines,” Kirkpatrick continues. “But there is a legitimate question as to the standard of care and the liability of sub-optimally trained users attempting something beyond their skill level.”
At Northwestern University Hospital, Trueger reports, the ultrasound director consistently drives home “the point that POC echocardiography is for very focused exams, with very focused questions“ and use of the equipment is restricted to operators who know how to use it to obtain the answers to such specific questions.
“We should remember, too, that for certain indications, POC echocardiography with handheld devices is not the right answer,” Johri observes. He cites the assessment of cardiac pump propulsion. POC echocardiography does not allow for the necessary multiple views, advanced analysis (via 3D and/or strain analysis) and multifaceted formula-based measurements.
What’s next?
With such challenges and potential complications in mind, efforts to provide POC echocardiography education have gotten underway. ASE has incorporated a POC echocardiography curriculum into its ASE University online portal, and the VascNet cardiovascular research network publishes POCUS Journal under the auspices of CINQ.
In the future, artificial intelligence (AI) also may help to overcome some of handheld POC echocardiography's challenges. AI will be leveraged to augment, rather than replace, human interpretation of the images, Cullen predicts. The usage model will involve “computer-assisted interpretation, but still require the human element,” and proper operation of the device will continue to affect results, he says.
Regardless of future developments, and even with training, the benefits of handheld POC echocardiography will not outweigh the challenges unless the modality remains an adjunct to standard echocardiography, Kirkpatrick says. “The point, as always, will be to get the right test for the right patient at the right time,” he explains. “This is often more difficult, but using cardiac ultrasound across the spectrum of care has the potential to improve our ability to reach this goal.”