COVID-19 infection is associated with several cardiac complications with high rates of adverse outcomes. Cardiac imaging has different utility in different clinical scenarios, and the importance of minimizing healthcare worker exposure should be considered.
Cardiac imaging should only be ordered if its benefits outweigh its risks, with anticipated changes in acute treatment and outcomes, and no suitable alternative of sufficient adequacy is available. Indications for advanced cardiac imaging for COVID-19 patients in the acute phase are limited, although follow-up imaging in the convalescent stage may provide prognostic importance in recovered COVID-19 patients with positive troponin or decompensated heart failure.
Since the initial cases in Wuhan, China in December 2019, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or 2019-nCoV), has rapidly become a global pandemic that has overwhelmed health systems, resulting in significant mortality.
Although COVID-19 primarily affects the lungs, a global inflammatory response involving multiple organs portends a poor prognosis. Cardiovascular complications of COVID-19 include acute myocardial injury in 12% to 28%, arrhythmias in 7% to 17%, and heart failure in about 20%, although whether they were caused by or exacerbated by COVID-19 remains unclear. Nevertheless, patients with a history of cardiovascular disease are at particularly high risk of adverse outcomes.
Previously, the decision to order cardiac imaging focused solely on balancing risks vs benefits at the patient level; however, the SARS-CoV-2 pandemic has resulted in an unprecedented impact on health-care delivery. Clinicians now must also consider the impact of potential exposure of healthcare workers, the concern for medical devices acting as fomites and causing nosocomial spread, and the feasibility of treatment options when determining diagnostic strategies for COVID-19 patients.
It is critically important to provide basic cardiorespiratory support to COVID-19 patients based on physical assessment with a thorough evaluation of risks and benefits before considering additional testing. Therefore, the following questions should be considered when ordering cardiac imaging:
- What is the specific clinical concern, and will the findings result in a substantial acute change in management?
- Will the benefits of cardiac imaging outweigh the risk of potential exposure of healthcare workers and nosocomial spread of virus?
- Are there alternative lower-risk options with sufficient accuracy to answer the clinical question?
- Can cardiac imaging be deferred until infectious risks have been mitigated or excluded?
Cardiac point-of-care ultrasonography (cPOCUS) should preferentially be performed in COVID-19 patients in the emergency room and intensive care unit by trained users when indicated. When there is uncertainty regarding the imaging findings, cPOCUS images should be reviewed with a certified cardiologist.
Images should be reviewed in conjunction with any past echocardiograms and recent chest computed tomography (CT) scans (for delineation of the presence of pericardial effusion, coronary artery calcification, and cardiac chamber sizes) to determine acute findings and need for focused/limited echocardiography.
Transthoracic echocardiography (TTE) examination protocols should be limited to decrease exposure time, but thorough enough to answer the clinical questions at hand and prevent need for repeat studies.
Advanced imaging techniques such as transesophageal echocardiography (TEE), cardiac computed tomography (CCT), or cardiac magnetic resonance imaging (CMR) have limited utility in the acute infectious phase for most hospitalized and acutely ill COVID-19 patients, since these are not likely to result in significant changes in acute management.
TEE carries a high aerosolization risk from patients gagging or coughing, and should be avoided unless absolutely critical for diagnosis. TTE with off-axis views, use of contrast agents, or CCT with contrast for left atrial appendage thrombus assessment may occasionally serve as adequate alternatives.
Infection-control precautions related to cardiac imaging should be followed with regard to equipment, personnel, protection, and location, which are outside the scope of this article.
Cardiac imaging should be delayed until outpatient follow-up of COVID-19 patients with suspected subacute clinical myocardial involvement. However, given the uncertainty regarding the duration of viral shedding, the development of strategic work-flow for outpatient cardiac imaging in convalescent COVID-19 patients should be considered and developed.
This commentary provides general recommendations for cardiac imaging by outlining 4 important clinical scenarios where cardiac imaging may be useful or controversial in hospitalized COVID-19 patients.