Detection of paroxysmal atrial fibrillation with transtelephonic EKG in TIA or stroke patients

Background: Paroxysmal atrial fibrillation (PAF) may remain underdiagnosed after stroke, as suggested by long-duration EKG monitoring. Here we report the sensitivity of transtelephonic EKG monitoring (TTM) for detection of PAF in patients following a recent stroke or TIA and a negative 24-hour Holter. Methods: We analyzed data from 98 consecutive patients with TTM and noncardioembolic TOAST stroke (n = 78) or TIA (n = 20). Most were cryptogenic events (82%). Patients started TTM 0.8 months (interquartile range 0.4-2.5) after the indexed event and randomly recorded about 1 EKG per day for 1 month. Univariate and multivariate analyses were run to identify PAF predictors. Results: Seventeen PAF episodes were detected in 9.2% (9/98) of the patients. The estimated duration of PAF episodes ranged from 4 to 72 hours. Two predictors were identified: premature atrial ectopic beats (more than 100) in 24-hour routine Holter (odds ratio [OR] = 11.0; 95% confidence interval [CI] 1.9-62; p = 0.007) and nonlacunar anterior circulation DWI hypersignals (OR = 9.9; 95% CI 1.1-90.6; p = 0.04). The PAF detection rate varied from 42.6% for patients meeting both criteria to 0% for patients with neither of them. Conclusions: Transtelephonic EKG monitoring increases detection rate of paroxysmal atrial fibrillation in stroke and TIA patients whose 24-hour Holter result was negative, especially if they had frequent premature atrial ectopic beats, recent anterior circulation infarct on MRI, or both. Neurology (R) 2010; 74: 1666-1670