Echocardiographic detection of transpulmonary bubble transit during coronavirus-2019 disease (COVID-19)

Background

Transpulmonary bubble transit (TPBT) detected with contrast echocardiography is reported as a sign of intrapulmonary arteriovenous shunt. However, its pathological meaning is not clear during coronavirus-2019 disease (COVID-19) related acute respiratory distress syndrome (ARDS). Our aim was to determine the prevalence and clinical significance of TPBT detection during COVID-19 related ARDS.

Methods

We carried out a prospective observational study performed in a high complexity intensive care unit from Argentina. Patients with COVID-19 related ARDS underwent transthoracic echocardiography with saline contrast. Moderate-to-large TPBT was defined as right-to-left passage of at least twelve bubbles to left chambers after at least three cardiac cycles and complete opacification of the right atrium.

Results

We analyzed the results of 28 patients (24 men and 4 women). Seventy-five percent of the patients received invasive mechanical ventilation. Moderate-to-large TPBT was detected in 1 patient (3.5%). Among the 27 patients without significant TPBT, 23 had no TPBT and 4 had a minor TPBT. TPBT was not associated with invasive mechanical ventilation requirement (p = 0.5737) nor in-hospital mortality (p = 1).

Conclusions

TPBT was not associated with severe hypoxemia or invasive mechanical ventilation requirement, although more studies are needed to further clarify its contributing role in COVID-19 hypoxemia.