Nurse Led Smartphone Electrographic Monitoring for Atrial Fibrillation after Ischemic Stroke: SPOT-AF

Abstract

Background and Purpose Paroxysmal atrial fibrillation (PAF) underlying acute stroke frequently evades detection by standard practice, considered to be a combination of routine electrocardiogram (ECG) monitoring, and 24-hour Holter recordings. We hypothesized that nurse-led in-hospital intermittent monitoring approach would increase PAF detection rate.Methods We recruited patients hospitalised for stroke/transient ischemic attack, without history of atrial fibrillation (AF), in a prospective multi-centre observational study. Patients were monitored using a smartphone-enabled handheld ECG (iECG) during routine nursing observations, and underwent 24-hour Holter monitoring according to local practice. The primary outcome was comparison of AF detection by nurse-led iECG versus Holter monitoring in patients who received both tests: secondary outcome was oral anticoagulant commencement at 3-month following PAF detection.Results One thousand and seventy-nine patients underwent iECG monitoring: 294 had iECG and Holter monitoring. AF was detected in 25/294 (8.5%) by iECG, and 8/294 (2.8%) by 24-hour Holter recordings (<i>P</i><0.001). Median duration from stroke onset to AF detection for iECG was 3 days (interquartile range [IQR], 2 to 6) compared with 7 days (IQR, 6 to 10) for Holter recordings (<i>P</i>=0.02). Of 25 patients with AF detected by iECG, 11 were commenced on oral anticoagulant, compared to 5/8 for Holter. AF was detected in 8.8% (69/785 patients) who underwent iECG recordings only (<i>P</i>=0.8 vs. those who had both iECG and 24-hour Holter).Conclusions Nurse-led in-hospital iECG surveillance after stroke is feasible and effective and detects more PAF earlier and more frequently than routine 24-hour Holter recordings. Screening with iECG could be incorporated into routine post-stroke nursing observations to increase diagnosis of PAF, and facilitate institution of guideline-recommended anticoagulation.

Clinical Implications of Atrial Fibrillation Detection Using Wearable Devices in Patients With Cryptogenic Stroke (CANDLE-AF) Trial: Design and Rationale

“…The sample-size calculation is based on the primary endpoint: “the detection probability for each group.” The detection probability was assumed as standard treatment: 2.5%, smartphone recorder: 8.5%, single-lead device: 14.5%, based on the SPOT-AF trial ( 13 ) and a previous assessment of a simulation in the CRYSTAL-AF trial ( 18 ). Non-inferiority margin was assumed to be 2.3% conservatively based on the difference in expected detection rates between single-lead device (14.5%) and smartphone-based device (8.5%) ( 13 , 18 ). First, for determining the single-lead device's superiority to standard strategy at a significance level (alpha) of 5%, power (1-beta) of 80%, and margin of 2.3%, we calculated that 108 participants are needed in each group, assuming a 10% drop-out rate.…”

“…Studies such as the Apple Heart Study ( 10 ), REHEARSE-AF (REmote HEArt Rhythm Sampling using the AliveCor heart monitor to scrEen for Atrial Fibrillation) ( 11 ), and the SCREEN-AF (SCREENing for Atrial Fibrillation) ( 12 ) proved the usefulness of single-lead ECG, their results were based on data from the general population and not data that was specifically obtained from patients with an ischemic stroke or transient ischemic attack (TIA). In 2020, a study of nurse-led monitoring during stroke (SPOT-AF) demonstrated the feasibility and efficacy of a single-lead ECG recorder for post-stroke AF detection ( 13 ). A prospective study for comparing the event recorder (2 times daily) with a 7-day Holter monitor is ongoing ( 14 ).…”

2021 Asia Pacific Heart Rhythm Society (APHRS) practice guidance on atrial fibrillation screening

“…supporting the use of handheld ECG devices in the stroke unit to screen for AF poststroke, 106,107 which may be of particular relevance to the Asia Pacific region and could be used in places without telemetry.…”

Searching for atrial fibrillation post-stroke with prolonged monitoring: Do it early, but should we be looking for something else?

“…The timing of monitoring is crucial, as identification that AF was the likely cause of stroke will change treatment from antiplatelets to oral anticoagulants. Early monitoring in the stroke unit is not always possible, but when nurses do monitor for AF systematically, a higher rate of AF detection than usual care is observed [3] . Unfortunately, even in high income countries where telemetry is available, ECG monitoring is not always performed, often due to patients being absent for multiple investigations including imaging.…”

“…If telemetry is performed, stroke unit nurses and even medical staff may not be experienced in arrhythmia diagnosis. Furthermore, although standard practice is a 24-hour Holter performed after discharge, only ~25% of patients receive this [3] , [4] . Thus, many cases of paroxysmal AF go unrecognised in this crucial early post-stroke period.…”