Editorial 

Can Transesophageal Echocardiography–Guided CPR Improve Out-of-Hospital Cardiac Arrest Outcomes?

Teva D. Brender, Tracy Y. Wang, Sharon K. Inouye, et al

JAMA Intern Med Published Online: March 23, 2026

doi: 10.1001/jamainternmed.2026.0115

Worldwide, an estimated 3.8 million persons experience an out-of-hospital cardiac arrest (OHCA) annually.¹ In the United States, only 8.2% of individuals with an OHCA survive with a favorable neurological outcome.² Despite higher rates of bystander cardiopulmonary resuscitation (CPR) and early use of automated external defibrillators,² survival has only improved modestly from 14.4 to 15.2 per 100 000 person-years over the last 20 years.³

The American Heart Association recommends that manual compressions be performed with the rescuer’s hand positioned at the center of the patient’s chest over the lower half of the sternum.² However, studies using transesophageal echocardiography (TEE) show that such positioning produces an area of maximal compression over the aortic root rather than the left ventricle about half of the time.⁴ Animal studies have demonstrated that maximizing left ventricle compression while minimizing aortic root compression during CPR increases stroke volume and results in higher rates of return to spontaneous circulation.⁵

In JAMA Internal Medicine, Chu and colleagues⁶ conducted a pragmatic, cluster-randomized clinical trial to test whether TEE-guided mechanical CPR would increase rates of return to spontaneous circulation in adult patients with nontraumatic OHCA. Conducted at a single emergency department in Taiwan, 132 patients were randomized to receive either TEE-guided or guideline-recommended CPR. In the intervention group, the research team performed TEE to continuously monitor the area of maximal compression to target compressions to the left ventricle and avoid the aortic root. There was no difference in the primary outcome of return to spontaneous circulation (44% vs 39%; cluster-adjusted odds ratio, 1.21; 95% CI, 0.64-2.29). While observed end tidal carbon dioxide levels (an indication of effective compressions and pulmonary perfusion) were higher in the TEE-guided group from 11 to 20 minutes after emergency department arrival, all secondary (survival to intensive care unit admission, survival to hospital discharge, and discharge with favorable neurological outcome) and safety (chest compression fraction, resuscitation-related complications) outcomes did not differ between groups.

As noted by the authors,⁶ several factors contributed to these null results. First, patients had prolonged out-of-hospital arrest (mean 30 minutes) and were very sick upon arrival to the emergency department (mean pH, 6.85). No patients survived to discharge with a favorable neurologic outcome (cerebral performance category ≤2), a lower proportion than other studies of OHCA.² Second, the study may have been underpowered: based on an observed 5% difference in rates of return to spontaneous circulation, a post hoc sample size analysis suggested that more than 4000 patients would need to be randomized to observe a statistically significant treatment effect. Third, 11% of patients in the TEE-guided CPR group did not receive TEE, and left ventricle–targeted compression was achieved in only 64%. Highlighting the observed hemodynamic benefits and no difference in resuscitation-related complications, the authors call for larger studies and suggest that integrating TEE-guided CPR into the out-of-hospital setting may yield clinical benefits. However, it is important to note that much larger samples would be required to assure this approach does not lead to harms.

Even if proven effective, implementation of TEE-guided CPR for OHCA—which requires trained operators and specialized equipment—faces considerable barriers. The American College of Emergency Physicians recommends TEE operators undergo a combination of didactic and hands-on training as well as examinations with live or high-fidelity simulation models⁷; however, the field lacks consensus regarding specific training, evaluation, and credentialing requirements.⁸ While TEE is currently used in the ED, financial and logistical concerns are frequent impediments to expanded use, including TEE transducer acquisition cost, the need for high-level disinfection procedures, insurance coverage, and high-fidelity simulator expenses.⁸

While out-of-hospital TEE-guided CPR may provide earlier and more effective resuscitation, its feasibility and utility depend on regional practice. Taiwan, like the United States, uses a paramedic-led emergency response model focused on rapid hospital transfer after initial stabilization (ie, “scoop and run”), whereas in many European countries, a physician-led system provides extended out-of-hospital stabilization and treatment (ie, “stay and play”).⁹ Local training, licensing, and certification requirements may dictate whether TEE is within the relevant clinicians’ scope of practice. The study by Chu and colleagues⁶ predominantly used a portable, automated chest compression system; in the United States, the rate of mechanical CPR for OHCA, while rising, is less than 10%.¹⁰ It remains to be determined whether mechanical or manual compressions are preferable in TEE-guided CPR. In the out-of-hospital setting, use of mechanical CPR could minimize the need for human chest compressors, allowing for the inclusion of a skilled clinician to operate the TEE probe without adding more members to the resuscitation team. Another trade-off to consider is that 80% of the 45 participants required repositioning of the location of chest compressions based on TEE guidance, and this repositioning may be more feasible and effective with manual chest compressions compared with a mechanical CPR device.

The study by Chu et al⁶ is a novel, well-conducted, hypothesis-driven investigation that, despite finding no clinical benefit for TEE-guided CPR, will help guide subsequent interventions and investigations. Perhaps one of the most important takeaways is that TEE-guided CPR may be most appropriate in the inpatient setting (where trained operators and specialized equipment are already available) to improve outcomes for in-hospital cardiac arrest; however, this will need to be evaluated in future studies. While the study focused exclusively on using TEE to guide compression location, additional benefits, such as aiding in the diagnosis of aortic dissection, pericardial effusion, or other potentially reversible causes of arrest, might be considered in the overall decision to incorporate TEE into resuscitation. Future research will help clarify the utility, feasibility, and safety of TEE-guided CPR, including which settings and patient populations have a sufficiently high likelihood of functional recovery to justify the addition of this resource-intensive intervention.