DISCUSSION AND CONCLUSION
Cardiac manifestations of COVID-19 ACS are due to coronary thrombosis or
acute plaque rupture from systemic inflammation and catecholamine surge
[2, 3]. For ACS due to plaque rupture, it is recommended that dual
anti-platelet therapy and full-dose anticoagulation be administered in
the acute setting per the American College of Cardiology (ACC)/American
Heart Association (AHA) and the European Society of Cardiology (ESC)
guidelines [4]. There are currently no specific guidelines on the
anticoagulant used or the duration of anticoagulation in the setting of
coronary thrombosis and/or LV thrombosis related to COVID-19.
As LV thrombus is not an uncommon complication of an acute myocardial
infarction, the 2013 ACC/AHA STEMI guidelines recommend oral
anticoagulation (OAC) use in setting of STEMI with anterior apical
akinesis or dyskinesis to prevent the thrombus formation for 3 months,
aiming for a lower international normalized ratio (INR) of 2.0-2.5
[5]. The 2017 ESC STEMI guidelines recommend OAC for up to 6 months
with final duration guided by a repeat TTE, risk of bleeding, and need
for concomitant antiplatelet therapy [6]. The ACTION Study Group
also concluded that anticoagulation for LV thrombus for at least 3
months was associated with a lower risk of major cardiovascular events
or all-cause mortality [7].
There have not been any large prospective or direct comparison studies
looking at direct OAC (DOAC) versus warfarin for treatment of LV
thrombus. One metanalysis did show that DOACs appear to be non-inferior
to warfarin without any statistical difference in stroke or bleeding
complications when treating for LV thrombus [8].
There have been cases that reported resolution of the LV thrombus in the
setting of COVID-19 infection prior to the 3-month mark. One reported
resolution on a 1-month follow-up TTE while on warfarin [9] while
another reported resolution at 10 days on low molecular weight heparin
[10]. Our patient had a large LV thrombus burden that resolved
within 2 months with warfarin use.
As such, a shorter duration of anticoagulation under close supervision
should be considered in patients with COVID-19 related
cardioembolic/thrombotic events, guided by echocardiographic imaging.
Such imaging would require a thorough sweep of the left ventricle in
on-axis and off-axis views so as to not miss any residual thrombi.
Prospective data about proper OAC regimen and duration is still needed.