Amidst the coronavirus disease-2019 (COVID-19) outbreak, elective aerosolizing procedures such as transesophageal echocardiography (TEE) should be deferred as the procedure provokes coughing and gagging, which can cause aerosolization of the virus (1). The American Society of Echocardiography recommends applying personal protective equipment when performing TEE in symptomatic patients with suspected/confirmed COVID-19. The risks and benefits of TEE should be considered for both symptomatic and asymptomatic COVID-19 patients (1).
In atrial fibrillation patients undergoing left atrial appendage closure (LAAC), TEE is typically performed at 45 days to assess peri-device flow <5 mm and an absence of device-related thrombus (DRT) before oral anticoagulation (OAC) is discontinued. We sought to investigate whether a 45-day TEE is absolutely necessary for patients who underwent LAAC amid the COVID-19 pandemic (2).
We retrospectively studied 200 patients who underwent a successful WATCHMAN procedure in a tertiary hospital (from June 2016 to June 2019). Upon discharge, patients were maintained on OAC and aspirin. We aimed to assess TEE measured peri-device flow at the time of implantation and at 45 days. Institutional review board approval was obtained. The mean age was 75.9 ± 8.3 years, and 42.9% of patients were women. The mean CHA2DS2-VASc and HAS-BLED scores were 4.8 ± 1.6 and 2.9 ± 0.9, respectively. Patients were discharged more frequently on direct oral anticoagulants (DOACs) (77.5%) as opposed to warfarin (22.0%). At the time of the WATCHMAN procedure, 189 of 200 patients (94.5%) had an absence of peri-device flow, and 11 of 200 (5.5%) had peri-device flow 1 to 5 mm.
Among 189 patients without peri-device flow during the procedure, 180 underwent TEE at 45 days; where 126 of 180 patients (70.0%) had an absence of peri-device flow, 53 of 180 (29.4%) had flow 1 to 5 mm, and 1 of 180 (0.6%) had significant peri-device flow >5 mm (Figure 1 ). Among 11 patients with peri-device flow 1 to 5 mm at the time of the procedure, 9 underwent TEE at 45 days; where 4 of 9 patients (44.4%) had an absence of peri-device flow, 5 of 9 (55.6%) had flow 1 to 5 mm, and 0 of 9 (0%) had peri-device flow >5 mm. No patients had DRT on 45-day TEE.
In the PROTECT-AF (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation) trial, peri-device flow >3 mm was observed in 13% and 12% of patients on 45-day and 1-year TEE, respectively. However, the more recent EWOLUTION (Evaluating Real-Life Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology) study showed that significant peri-device flow >5 mm occurred only in 1% of patients on 1-year TEE. In our study, 1 patient (0.5%) developed significant peri-device flow on 45-day TEE, and none had DRT.
For WATCHMAN programs that deviate from standard warfarin regimen post-LAAC, DRT is more common with single/dual antiplatelet therapy than OAC (warfarin and DOACs) (3). The rates of DRT were similar in patients receiving DOAC (0.9%) compared with warfarin (0.5%) in a retrospective multicenter study (4). Thus, a 45-day assessment may be more relevant in patients receiving single/dual antiplatelet therapy post-LAAC. Additionally, it calls into question the current practice of assessing DRT while on OAC at 45 days. It may be more reasonable to assess for DRT after discontinuation of OAC. This specific question requires further investigation.
In this retrospective analysis, we showed that the incidence of significant peri-device flow and DRT at 45 days is very low. Thus, a 45-day TEE post-WATCHMAN implantation may not be necessary for all patients, and OAC may be safely discontinued at 45 days without a TEE. Currently, the National Cardiovascular Data Registry Left Atrial Appendage Occlusion Registry requires documentation of device closure and absence of DRT at 45 days post-LAAC. Computed tomography is a reasonable alternative to TEE for device surveillance (5). In our opinion (not supported by the present study), the rationale for foregoing a 45-day TEE should also extend to the baseline TEE before LAAC. Use of computed tomography may be considered. Amid the COVID-19 pandemic, deferring 45-day TEE post-WATCHMAN implantation has the potential to minimize use of personal protective equipment and reduce preventable risks of viral transmission. Prospective trials are warranted to see whether this practice should be reconsidered even after the pandemic subsides (2).