Literature Review
VIENNA—Handheld ECG monitors offer a practical, noninvasive means of detecting atrial fibrillation in patients who have been diagnosed with ischemic stroke or transient ischemic attack (TIA), according to a retrospective hospital-based study presented at the 24th European Stroke Conference.
The results showed an overall detection rate of 7.6%, which is in the same range seen in previous studies of handheld ECG monitors, but higher than the detection rate in most studies that used 24-hour Holter monitoring, said study investigator Dr. Ann-Sofie Olsson of Hallands Hospital in Halmstad, Sweden.
The retrospective study included data on 356 patients who presented to the hospital for ischemic stroke or TIA and underwent intermittent handheld ECG testing to monitor for atrial fibrillation. The mean age of patients was 66, and 53% of patients were male. In all, 46% of patients were diagnosed with ischemic stroke and 56% with TIA. The mean baseline CHA2DS2-VASc score was 4.2, suggesting that patients were at moderate risk of subsequent atrial fibrillation-related stroke.
The ECG monitor used in the study consisted of a small, lightweight plastic box that patients held by two thumb sensors for 10, 20, or 30 seconds. Measurements were taken twice per day (ie, in the morning and in the 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 viewed with 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 had a positive result. Although the investigators found no statistically significant difference in atrial fibrillation detection rates between men (8.5%) and women (6.5%), detection rates were higher among patients with ischemic stroke, compared with patients with TIA (11% vs 5%). The researchers also observed a trend toward better detection rates in patients age 65 or older, compared with younger patients. The detection rates were 8.8% and 4.2%, respectively.
Although more patients in the study cohort had TIA than stroke, the detection rate of atrial fibrillation was lower among patients with TIA. “It is natural to ask ourselves whether we can improve the detection rates by selecting higher-risk patients,” Dr. Olsson said.
“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. The oldest patient in the study was age 90. The monitor used in the study had a sensitivity of 96% and a specificity of 92%.
—Sara Freeman
