Thromboembolic risk in 16 274 atrial fibrillation patients undergoing direct current cardioversion with and without oral anticoagulant therapy

TY - JOUR

T1 - Thromboembolic risk in 16 274 atrial fibrillation patients undergoing direct current cardioversion with and without oral anticoagulant therapy

AU - Hansen, Morten Lock

AU - Jepsen, Rikke Malene H G

AU - Olesen, Jonas Bjerring

AU - Ruwald, Martin Huth

AU - Karasoy, Deniz

AU - Gislason, Gunnar Hilmar

AU - Hansen, Jim

AU - Køber, Lars

AU - Husted, Steen

AU - Torp-Pedersen, Christian

N1 - Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: [email protected].

PY - 2014/11/25

Y1 - 2014/11/25

N2 - AIMS: To study the risk of thromboembolism in a nationwide cohort of atrial fibrillation patients undergoing direct current (DC) cardioversion with or without oral anticoagulant coverage.METHODS AND RESULTS: A retrospective study of 16 274 patients in Denmark discharged from hospital after a first-time DC cardioversion for atrial fibrillation between 2000 and 2008. Use of oral anticoagulant therapy within 90 days prior and 360 days after DC cardioversion was obtained from the Danish Register of Medicinal Product Statistics. The risk of thromboembolism was estimated by calculating incidence rates and by multivariable adjusted Cox proportional-hazard models. During the initial 30 days following discharge, the thromboembolic incidence rate was 10.33 per 100 patient-years for the no prior oral anticoagulant therapy group [n = 5084 (31.2%)], as compared with 4.00 per 100 patient-years for the prior oral anticoagulant therapy group [n = 11 190 (68.8%)], [hazard ratio associated with no prior oral anticoagulant therapy was 2.25; 95% confidence interval (CI), 1.43-3.53]. Thromboembolic risk stratification by the CHADS2 and CHA2DS2-VASc scores did not change the results. Hazard ratio with no oral anticoagulant therapy was 2.21; 95% CI, 0.79-6.77 and 2.40; 95% CI, 1.46-3.95 with CHA2DS2-VASc score 0-1 and CHA2DS2-VASc score 2 or more, respectively.CONCLUSION: Direct current cardioversion for atrial fibrillation without oral anticoagulation is associated with a high risk of thromboembolism. Notably, the risk is high in the initial period after cardioversion, indicating a hazardous association between DC cardioversion without anticoagulation and thromboembolism.

AB - AIMS: To study the risk of thromboembolism in a nationwide cohort of atrial fibrillation patients undergoing direct current (DC) cardioversion with or without oral anticoagulant coverage.METHODS AND RESULTS: A retrospective study of 16 274 patients in Denmark discharged from hospital after a first-time DC cardioversion for atrial fibrillation between 2000 and 2008. Use of oral anticoagulant therapy within 90 days prior and 360 days after DC cardioversion was obtained from the Danish Register of Medicinal Product Statistics. The risk of thromboembolism was estimated by calculating incidence rates and by multivariable adjusted Cox proportional-hazard models. During the initial 30 days following discharge, the thromboembolic incidence rate was 10.33 per 100 patient-years for the no prior oral anticoagulant therapy group [n = 5084 (31.2%)], as compared with 4.00 per 100 patient-years for the prior oral anticoagulant therapy group [n = 11 190 (68.8%)], [hazard ratio associated with no prior oral anticoagulant therapy was 2.25; 95% confidence interval (CI), 1.43-3.53]. Thromboembolic risk stratification by the CHADS2 and CHA2DS2-VASc scores did not change the results. Hazard ratio with no oral anticoagulant therapy was 2.21; 95% CI, 0.79-6.77 and 2.40; 95% CI, 1.46-3.95 with CHA2DS2-VASc score 0-1 and CHA2DS2-VASc score 2 or more, respectively.CONCLUSION: Direct current cardioversion for atrial fibrillation without oral anticoagulation is associated with a high risk of thromboembolism. Notably, the risk is high in the initial period after cardioversion, indicating a hazardous association between DC cardioversion without anticoagulation and thromboembolism.

KW - Administration, Oral

KW - Aged

KW - Aged, 80 and over

KW - Anticoagulants

KW - Atrial Fibrillation

KW - Combined Modality Therapy

KW - Comorbidity

KW - Defibrillators, Implantable

KW - Denmark

KW - Female

KW - Hospitalization

KW - Humans

KW - Incidence

KW - Male

KW - Retrospective Studies

KW - Risk Assessment

KW - Survival Rate

KW - Thromboembolism

U2 - 10.1093/europace/euu189

DO - 10.1093/europace/euu189

M3 - Journal article

C2 - 25231909

SN - 1099-5129

VL - 17

SP - 18

EP - 23

JO - Europace

JF - Europace

IS - 1

ER -