Prevalence of Atrial Fibrillation and Antithrombotic Prophylaxis in Emergency Department Patients

Abstract

Background and Purpose-The emergency department (ED), as the point of first medical contact for many complaints referable to atrial fibrillation (AF) and a common source of primary care, occupies a unique position to identify AF patients at risk of stroke. This study evaluates that potential by determining the prevalence of AF in an ED population and assessing antithrombotic use in those patients with recurrent AF. Methods-This was a multicenter, retrospective, cross-sectional study of consecutive records of ED patients with AF identified by ECG between January and June 1998. American Heart Association and modified Stroke Prevention in Atrial Fibrillation criteria established high-risk patients and contraindications to anticoagulation, respectively. Results-We identified 866 records with ECG-proven AF in 78 787 patient visits for an estimated prevalence of 1.10% (95% CI, 1.03 to 1.17). We found that 556 records had a prior history of AF; of these, 221 (40%) used warfarin alone, 155 (28%) had antiplatelet therapy alone, 28 (5%) used both, and 152 (27%) had no antithrombotic therapy identified. Sixty-eight patients (12%; 95% CI, 0.10 to 0.15) were warfarin eligible and without antithrombotic therapy. An additional 64 (12%; 95% CI, 0.09 to 0.14) had antiplatelet therapy alone. In warfarin-eligible patients, no differences were identified between the anticoagulated and nonanticoagulated groups on the basis of age, sex, or race. Of patients on warfarin with a measured international normalized ratio, 61% (95% CI, 0.55 to 0.67) were outside the AHA-recommended range of 2.0 to 3.0. Conclusions-AF is a common finding in an ED population. Many are warfarin eligible and untreated or undertreated.Methods to increase anticoagulant use in this at-risk population warrant further investigation.

Differences among Clinical Classification Schemes for Predicting Stroke in Atrial Fibrillation: Implications for Therapy in Daily Practice

“…Finally, our ED population had a high risk of stroke, and considering the devastating consequences of stroke in these patients, stroke prophylaxis must be initiated as soon as possible. Therefore, and according to other authors, 27 anticoagulants could be accurately prescribed by emergency physicians in patients with NVAF and high risk of stroke. Patients discharged from the ED should then be sent for cardiology consultation for further workup, whereas control of oral anticoagulation should be performed in the primary care setting.…”

“…Although carefully evaluated by the study group, we could be underestimating contraindications for anticoagulation, and this could contribute to the low prescription of anticoagulants in older patients with high risk of stroke. Other factors that could have an influence in the low prescription of anticoagulation in our study are physicians' distrust in the validity of clinical trials that support these CCSs, 30 the uncertainty about whether the CCSs' benefits are applicable to clinical practice, 31 or their reticence to initiate anticoagulation for older patients, 16,27,30,32 despite the available evidence. 33 In addition to this, in some cases, the emergency physicians could be following the recommendations of local clinical practice guides, and the rate of anticoagulation would vary as much as 13% to 100%, depending on the guideline used.…”

“…4,16 In our study, the prescription of anticoagulation as stroke prophylaxis by the treating physicians was insufficient and did not follow the risk stratification provided by any of the widespread CCSs. Although the efficacy of anticoagulation has been demonstrated in numerous clinical trials, 11 various studies have highlighted a low prescription in various daily practice settings such as hospitals, 24,25 primary care, 26 EDs, 16,27 and geriatric units. 28 Thus, in daily practice, anticoagulation is prescribed to only 15-44% of eligible patients, 29 consistent with the 24% of prescriptions found in our study.…”

“…27 Additionally, NVAF is the most frequently managed arrhythmia in the ED, and is often the point of first medical attention for patients with symptoms related to the arrhythmia. Finally, our ED population had a high risk of stroke, and considering the devastating consequences of stroke in these patients, stroke prophylaxis must be initiated as soon as possible.…”

"Fibrilação atrial e tratamento antitrombótico em pacientes atendidos em hospital especializado em cardiologia no Brasil"

“…Atualmente, as diretrizes nacionais e internacionais (34,35,36) Contudo, apesar da publicação das diretrizes nacionais e internacionais sedimentadas na medicina baseada em evidências, diversos estudos em todo o mundo têm alertado para o uso excessivamente baixo e inadequado da terapia antitrombótica nos pacientes com fibrilação atrial (38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50) . Razões abordadas nestes estudos para justificar tal fato incluem a inconveniência do tratamento pela necessidade de controles laboratoriais seriados, o temor dos médicos pela possibilidade de complicações hemorrágicas, baixa aderência dos pacientes ao tratamento, falta de conhecimento médico com relação às diretrizes existentes e o controle do RNI na maior parte das vezes precário, estando dentro dos níveis preconizados em menos de metade dos pacientes tratados (38)(39)(40)50) .…”