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 If no thrombus is found on TEE, the TEE probe is withdrawn, and patient is cardioverted.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.