SCREENING FOR ATRIAL-FIBRILLATION IN PRIMARY-CARE

Objective-To investigate a population of elderly people for atrial fib rillation and to determine how many of the cases identified might bene fit from treatment with anticoagulants. Methods-From a practice of fou r primary care physicians, 1422 patients aged 65 years and over were i dentified, of whom 1207 (85% of the total population) underwent electr ocardiographic screening to detect the presence of atrial fibrillation . Patients with the arrhythmia were further evaluated by echocardiogra phy and interview, to stratify their risk of stroke based on echocardi ographic and clinical risk factors, their perceived risk from anticoag ulation, and their attitude towards this treatment. Their primary care physician was also interviewed to determine the factors influencing t he prescription of anticoagulants.Results-The arrhythmia occurred in 6 5 patients (5.4% overall), its prevalence increasing markedly with age (2.3% in 65 to 69 years age group; 8.1% in those over 85). Warfarin w as being prescribed to 21.4% of these patients, although the findings of the study indicate that a further 20% were eligible for this treatm ent. Symptoms suggestive of cardiac failure were common (32.1%) and co existing pathology was often identified by cardiac ultrasound in these patients (left ventricular hypertrophy, 32.1%; impaired left ventricu lar contractility, 21.4%; left atrial dilatation, 80.4%; mitral annula r calcification, 42.9%; mitral stenosis, 7.1%; mitral regurgitation, 4 8.2%; aortic stenosis, 8.9%). In all but one case, the decision to ant icoagulate was based on the clinical rather than the echocardiographic findings. Conclusions-Individual risk-benefit assessment in elderly p atients with atrial fibrillation suggests that almost half (41.4%) are eligible for full anticoagulation with warfarin, whereas presently on ly one fifth are receiving this treatment. The decision to anticoagula te can be made on clinical grounds in most cases. If these results are confirmed, a doubling of the current number of patients taking antico agulants can be anticipated.