Discussion
This case is unique in that it highlights potential complication of LA
appendage thrombus formation with the current practice of TEE-guided
cardioversion, especially with the availability of newer anticoagulants
that provide rapid and effective anticoagulation. Following the
publication of ACUTE trial (1) that demonstrated the safety of
short-term anticoagulation followed by TEE-guided cardioversion and
anticoagulation in preventing thrombo-embolic risk, it is a common
practice for patients to undergo TEE-guided cardioversion after a brief
period of outpatient anticoagulation. This strategy shortens the
duration of afib and, in many cases, the total duration of
anticoagulation. If no thrombus is found on TEE, the TEE probe is
withdrawn, and patient is cardioverted. However, post-cardioversion
thrombo-embolic events occur even in patients without LA appendage
thrombus on TEE. Presence of spontaneous echo contrast is a predictor of
such events (2) and has been shown to worsen after cardioversion along
with transient atrial dysfunction (3). However, in our patient, the TEE
probe was left in due to multiple concerns, including significant
biatrial enlargement suggesting afib might be more chronic, the presence
of spontaneous contrast, unusual appendage anatomy with a dilated
appendage, and an elongated accessory lobe, along with the short
duration of anticoagulant therapy. In this context, we have previously
reported dissociation of atrial rhythm in the LA appendage body and
similar elongated accessory lobe and presence of a thrombus at the tip
of this accessory lobe in a patient with afib (4).
Indeed this patient demonstrated the formation of a large LA appendage
thrombus in the appendage accessory lobe that developed shortly after
cardioversion. Typically, the patient would have been discharged and may
have had a complication of a cardioembolic event. Our case highlights
that even with direct anticoagulants, there should be a waiting period
before cardioversion is performed, either with or without TEE guidance.
In a patient with a short duration of anticoagulation and particularly
adverse cardiac anatomy, as in our patient, TEE probe may be left in
during cardioversion so that LA appendage may be evaluated
post-cardioversion.