ABSTRACT
In patient with chronic nonvalvular atrial fibrillation [AF], the correlation between prothrombotic marker D-dimer, N-terminal pro-atrial natriuretic peptide [NT-ANP], and left atrial [LA] size is not completely understood also, the precise effect of hypercoagulability is not well known to date. Therefore, this study was performed to determine whether prothrombotic state presented by increase level of D-dimer in patients with chronic nonvalvular AF, as well as NT-ANP were correlated with left atrial size and risk of thromboembolic events. A 43 patients with chronic nonvalvular atrial fibrillation with prior cerebrovascular cardioembolic event and 35 without cardioembolic event were studied for echocardiographic LA size, D-dimer level and NT-ANP. the LA size and D-dimer were significantly high in patients with cardioembolic stroke than patients without cardioembolic stroke [P value <0,05], no significant difference in NT-ANP in both groups [P value >0.05], a positive linear correlation was found between the increased D-dimer level and LA size [r=0.42, P<0.01]. No correlation was found between NT-ANP level and the LA size. the present study concluded that the prothrombotic marker D-dimer is elevated in patient with chronic nonvalvular AF, this marker showed positive linear correlation to the left atrial size and cardioembolic risk of stroke making it a significant marker for risk stratification for those patient whom at high risk, the result also opened a rational for use of warfarin in those patient with elevated D-dimer