A number of new methods, including advanced technologies such as implantable cardiac monitors, are currently being investigated to improve atrial fibrillation (AF) detection in patients with cryptogenic stroke (see CRYSTAL-AF study for review). Despite such advances, however, there is still an unmet need for affordable, accessible, and cost-effective ways to diagnose AF after an ischemic stroke.
To address this need, Kallmunzer and colleagues (from Erlangen, Germany) conducted a feasibility study to evaluate the accuracy of patient measurement of radial artery pulse (MPP) as a simple noninvasive tool for detection of AF. After education on accurate measurement and how to detect AF via radial pulse, 256 patients and their relatives were prospectively enrolled and accuracy of AF detection by MPP was compared with simultaneously obtained blinded ECG.
The results of this preliminary proof-of-principle study were published in July 2014 in Neurology. Only 6 subjects or relatives reported false-positive results (2.7%) and the negative predictive value of self-AF screening by MPP was very high (90.0%). When health care providers or patients’ relatives performed the MPP, the sensitivity was 96.5% and 76.5% with a specificity of 94% and 92.9%, respectively. Eighty-nine percent of patients were able to perform MPP independently. However, the sensitivity of self-measurement was lower (54.1%) when patients themselves performed MPP, with a comparable specificity of 96.2%.
Notably, although MPP is an element of the screening recommendations for primary prevention, it has not been systematically studied in secondary prevention for stroke. These data provide convincing preliminary evidence that MPP screening may be an important tool for improving detection of occult AF after a cryptogenic stroke. However, despite the high negative predictive value, the larger study will confirm whether self-MPP will become a stand-alone screening tool or serve a role in combination with other tools for AF detection.
Kallmünzer B, Bobinger T, Kahl N, et al. Peripheral pulse measurement after ischemic stroke: a feasibility study. Neurology. 2014 Jul 23; [Epub ahead of print]. 10.1212/WNL.0000000000000690.