Wearable devices on par with conventional tools for cardiac monitoring after stroke

Electrocardiogram (ECG)- and photoplethysmography (PPG)-based wearable devices demonstrate effectiveness for paroxysmal atrial fibrillation (AF) detection following cryptogenic stroke or embolic stroke of undetermined source (ESUS) similar to that of conventional management, results of a Singapore study have shown.

“There is a range for devices currently approved by FDA and CE marked for use on patients, and ongoing clinical trials would provide further evidence on their efficacy, safety, and acceptability to patients,” the investigators said.

Currently, the consensus for AF diagnosis is >30 s on cardiac monitoring or 10 s on 12-lead ECG. Patients with this diagnosis should receive anticoagulation to reduce the risk of further ischaemic strokes, unless contraindicated. [Heart Rhythm 2007;4;816-861]

“Despite the lack of clear guidelines on the duration, timing, and use of device for cardiac monitoring postcryptogenic stroke, there is strong evidence that prolonged cardiac monitoring increases detection of subclinical AF, and implantable loop recorder (ILR) is considered the gold standard,” the investigators said. [Int J Cardiol Heart Vasc 2021;34;100780]

Wearable technology

In the present systematic review, the databases of PubMed, Embase, Scopus, and clinicaltrials.gov were searched on 21 July 2022 to identify studies that examined the use of wearable technology in patients with cryptogenic stroke or ESUS.

The investigators analysed the outcomes of AF detection. They then summarized literature reports on ECG-based (eg, external wearable, handheld, patch, mobile cardiac telemetry [MCT], smartwatch) and PPG-based devices (eg, smartwatch, smartphone).

Twenty-seven studies met the eligibility criteria. Of these, 10 were cohort studies, seven prospective trials, six case series, two case reports, and two randomized controlled trials. [Singapore Med J 2024;65:370-379]

Four studies compared wearable technology to Holter monitoring or ILR and found no significant differences (odds ratio, 2.35, 95 percent confidence interval [CI], 0.74‒7.48; I², 70 percent). AF was detected by external wearable devices in 20.7 percent of patients (95 percent CI, 14.9‒27.2; I², 76 percent) and by MCT in 9.6 percent (95 percent CI, 7.4‒11.9).

Other devices including patch sensors, handheld ECG recorders, and PPG-based smartphone apps also showed feasibility in the postcryptogenic stroke and post-ESUS setting.

Algorithms

“Wearable devices that are ECG- or PPG-based are effective for paroxysmal AF detection after cryptogenic stroke and ESUS, but further studies are needed to establish how they compare with Holter monitors and implantable loop recorder,” the investigators said.

The accuracy of wearable devices with automatic analysis using algorithms for rhythm detection is generally acceptable.

In a recent systematic review of 208 studies on AF detection using mobile health solutions, the sensitivity and specificity for ECG-based devices were as follows: 93.4 percent to 97.0 percent and 95.6 percent to 98.5 percent for patches, 96.3 percent and 98.2 percent for belts, and 94.0 percent to 98.0 percent and 76.0 percent to 95.0 percent for handheld devices, respectively. [Clin Res Cardiol 2022;111;479-491]

“Wearable technology adoption has been increasing year on year and is estimated to [have reached] more than 1 billion users in 2022, which may increase the acceptability and cost-effectiveness of wearable devices for cardiac monitoring of patients,” the investigators said. [Sensors (Basel) 2021;21;5589]