P1530 Dense spontaneous echo contrast and thrombus in patients on new oral anticoagulant and warfarin therapy: a retrospective audit

Abstract

Abstract Background Cardioembolic stroke is a known complication of atrial fibrillation (AF), which is increasing in global prevalence. Spontaneous echo contrast (SEC) in the left atrium (LA) is a precursor for thrombus formation detected on transesophageal echocardiography (TEE). There is limited data regarding the prevalence of dense SEC and/or left atrial thrombus (LAT) detected by TEE in patients on novel oral anticoagulants (NOACs) compared with Warfarin. Purpose To determine and compare the prevalence of dense SEC and/or LAT among patients with AF/atrial flutter undergoing TEE while on continuous NOAC or Warfarin therapy. Methods Retrospective analysis of prospectively entered data for all patients who were on continuous oral anticoagulants and underwent TEE with DC cardioversion, over a 9-year period (1st January 2011 to 31st December 2018) at a public teaching hospital in NSW, Australia. SEC was classified according to emptying flow velocities, as per the European Association of Cardiovascular Imaging guidelines. Results Among the 195 patients, 94 (48%) patients were on NOAC therapy (52% Apixaban, 25% Rivaroxaban, 23% Dabigatran) while 101 (52%) patients were on Warfarin. There was no difference in age (mean ± SD: 64 ± 12 vs. 65 ± 13, p = 0.71) or proportion of males (71% vs 69%, p = 0.76) between patients on NOAC therapy compared with Warfarin. However, the NOAC therapy group had a lower prevalence of ischaemic heart disease (IHD) (18% vs. 33%, p < 0.05) and chronic kidney disease (CKD) (2% vs. 19%, p < 0.001), in addition to a lower CHA2DS2-VASc score (2.1 ± 1.7 vs 2.7 ± 1.7, p = 0.03) and higher haemoglobin levels (145.3 ± 19 vs 133.8 ± 24, p = 0.001). The overall rate of dense SEC and/or LAT detected by TEE was 9.7%. There was no significant difference in the prevalence of dense SEC and/or LAT between patients on NOACs and Warfarin (6.4% vs. 12.9%, p = 0.13). On multivariable analysis of IHD, CKD, Warfarin, NOACs and CHA2DS2-VASc score, there was no significant difference in prevalence of SEC/LAT between Warfarin and NOACs. Conclusions In this study, 6.4% of patients on continuous NOACs and 12.9% of patients on Warfarin therapy had dense SEC and/or LAT detected by TEE. Although the trend towards higher rates of dense SEC and pre-thrombus in the Warfarin group did not reach statistical significance, it still holds clinical significance as these patients cannot be cardioverted. Therefore, these data support the need to consider anticoagulant optimisation in the overall management of patients with SEC.