VIENNA – Handheld ECG monitors offered a practical, noninvasive solution to detecting atrial fibrillation in patients who had been diagnosed with ischemic stroke or transient ischemic attack in a retrospective hospital-based study.
The results presented at the annual European Stroke Conference showed an overall detection rate of 7.6%, which is in the same range seen in previous studies of handheld ECG monitors but was higher than in most studies that used 24-hour Holter monitoring, said study investigator Dr. Ann-Sofie Olsson of Hallands Hospital Halmstead (Sweden).
The retrospective study included data on 356 patients who had been seen at the hospital for ischemic stroke or transient ischemic attack (TIA) and who had undergone intermittent handheld ECG testing to monitor for atrial fibrillation (AF). The mean age of patients was 66 years, 53% were male, and 46% were diagnosed with ischemic stroke and 56% with TIA. The mean baseline CHA2DS2-VASc score was 4.2, suggesting patients were at reasonably moderate risk of subsequent AF-related stroke.
The ECG monitor used consisted of a small, lightweight plastic box that patients held by two thumb sensors for 10, 20, or 30 seconds, with measurements taken twice a day (morning and evening) for 14 days. The sensors, which provided lead I of a standard ECG, provided information on atrial movement that was transmitted to a data server and was viewed via a web browser.
“We defined a positive investigation as either atrial fibrillation for a minimum of 10 seconds or a short, irregular supraventricular arrhythmia, Dr. Olsson explained.
Overall, 27 (7.6%) of the 356 patients evaluated had a positive result, with a 95% confidence interval ranging from 5.1% to 10.1%. While there was no statistically significant difference in AF detection rates between men (8.5%) and women (6.5%), detection rates were higher if patients had had an ischemic stroke rather than a TIA (11% vs. 5%, P = .032). There was also a trend (P = .051) for better detection rates in older (≥65 years) than younger (<65 years) patients, at 8.8% vs. 4.2%, respectively.
“It is natural to ask ourselves whether we can improve the detection rates by selecting higher-risk patients,” Dr. Olsson said, commenting on the lower detection rate seen in TIA patients despite there being more TIA cases in the study cohort.
“We saw high adherence to the monitoring; only six (1.5%) patients did not complete the investigation,” said Dr. Olsson, noting that older age did not seem to be an obstacle to performing the ECG with the handheld monitor as the oldest patient in the study was 90 years.
Dr. Olsson noted that the monitor used in the study had a sensitivity of 96% and a specificity of 92%.
Dr. Olsson reported having no relevant financial disclosures.