Feasibility of Extended Ambulatory Electrocardiogram Monitoring to Identify Silent Atrial Fibrillation in High-risk Patients: The Screening Study for Undiagnosed Atrial Fibrillation (STUDY-AF)
Turakhia, M., et al. (2015)
Clinical Cardiology Journal
Background: Identiﬁcation of silent atrial ﬁbrillation (AF) could prevent stroke and other sequelae. Hypothesis: Screening for AF using continuous ambulatory electrocardiographic (ECG) monitoring can detect silent AF in asymptomatic in patients with known risk factors.
Methods: We performed a single-center prospective screening study using a wearable patch-based device that provides up to 2 weeks of continuous ambulatory ECG monitoring (iRhythm Technologies, Inc.). Inclusion criteria were age ≥55 years and ≥2 of the following risk factors: coronary disease, heart failure, hypertension, diabetes, sleep apnea. We excluded patients with prior AF, stroke, transient ischemic attack, implantable pacemaker or deﬁbrillator, or with palpitations or syncope in the prior year.
Results: Out of 75 subjects (all male, age 69 ±8.0 years; ejection fraction 57% ±8.7%), AF was detected in 4 subjects (5.3%; AF burden 28% ±48%). Atrial tachycardia (AT) was present in 67% (≥4 beats), 44% (≥8 beats), and 6.7% (≥60 seconds) of subjects. The combined diagnostic yield of sustained AT/AF was 11%. In subjects without sustained AT/AF, 11 (16%) had ≥30 supraventricular ectopic complexes per hour.
Conclusions: Outpatient extended ECG screening for asymptomatic AF is feasible, with AF identiﬁed in 1 in 20 subjects and sustained AT/AF identiﬁed in 1 in 9 subjects, respectively. We also found a high prevalence of asymptomatic AT and frequent supraventricular ectopic complexes, which may be relevant to development of AF or stroke. If conﬁrmed in a larger study, primary screening for AF could have a signiﬁcant impact on public health.