A short cut review was carried out to establish whether a negative D-dimer will accurately rule out an atrial thrombus in a patient presenting with atrial fibrillation. Ten papers seemed relevant to the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that a negative D-dimer suggests that it is safe to cardiovert a patient with recent onset of atrial fibrillation.

Three part question

In [patients with atrial fibrillation being considered for electrical or pharmacologic cardioversion] does [measurement of D-dimer] allow [exclusion of atrial thrombus]?

Clinical scenario

A 45-year-old man presents to the emergency department with a 48 hour history of palpitations, postural light-headedness and exertional dyspnoea. ECG demonstrates atrial fibrillation (AF) at a rate of 130 beats/minute. There are no apparent reversible causes following history, examination, chest radiography, urinalysis and haematological and biochemical screening.You feel that pharmacologic or electrical cardioversion to sinus rhythm rather than rate control would be most beneficial to the patient, but as you are aware of the possibility of atrial thrombus and systemic embolism you opt for rate control and refer for anticoagulation. You wonder if measuring D-dimer, a product of clot breakdown, would have allowed accurate exclusion of atrial thrombus, thus enabling the safe acute administration of …