Evidence-Based Case Report: The Use of D-Dimer Assay to Exclude Left Atrial Thrombus in Patient with Atrial Fibrillation >48 Hours

Abstract

Patients with atrial fibrillation (AF) for >48 hours who are a candidate for cardioversion should have transesophageal echocardiography (TEE) performed to exclude left atrial thrombus (LAT) that may cause systemic thromboembolism upon conversion to sinus rhythm. However, TEE facilities were limited mainly in developing countries and left atrial appendage may be a challenge to visualize by transthoracic echocardiography. In this article, we would like to discuss a patient that presented with AF >48 hours and is a candidate for cardioversion, however, there is no TEE at the facility. We performed a comprehensive search on whether d-dimer assay can be used to exclude LAT in this patient in order to perform safe cardioversion. Case IllustrationA 50 years-old man presented with exertional dyspnea and palpitation for 72 hours prior to admission. There was no chest pain, episode of syncope, or edema. The patient was limited by symptoms but hemodynamically stable. Electrocardiography showed AF with a ventricular rate of 140x/minute. The patient has a history of hypertension on treatment with captopril. There was no history of stroke and heart failure. There was no apparent reversible cause of AF based on a panel of laboratory examinations (Including a D-Dimer <250 ng/ml DDU). Based on CHADVASC scoring, this patient has a score of 1, a 0 Wells DVT score for thromboembolic probability, and a HAS-BLED Score of 1 for bleeding probability while on anticoagulants. After considerations, it was decided that cardioversion into sinus rhythm would be the best approach in this patient. This patient has an AF >48 hours of onset, hence, LAT should be excluded by the use of TEE. Unfortunately, there was no TEE facility nearby. The patient was anticoagulated for weeks, cardioversion was performed, and AF was converted into sinus rhythm. On 6 months' follow-up, the patient remained in sinus rhythm. DiscussionWe The clinical question is whether d-dimer assay can be used to exclude the diagnosis of LAT in patients presenting with AF >48 hours without the use of TEE or should patients be anticoagulated for weeks before attempting cardioversion. To answer this question, two independent authors (E.Y and V.C) performed a comprehensive and systematic search on studies on the use of D-Dimer assay to exclude the left atrial thrombus in patients with atrial fibrillation

AFibNet: an implementation of atrial fibrillation detection with convolutional neural network

“…AF is the most prevalent severe abnormal heart rhythm associated with a fast heart rate. It refers to an abnormal, rapid, and non-synchronized muscle fiber contraction with complex patophysiology [4][5][6][7], and is recognized as an independent risk factor for stroke, with important clinical and economic consequences. Diagnosing the symptoms is important before treatment of this severe disease; however, existing commercial ECG devices for AF detection methods still show actual misdiagnosis rates.…”