Community atrial fibrillation (AFib) screening by smartphone ECG is effective in identifying patients with newly diagnosed AFib, according to results from the AFinder study presented at ESC Congress 2017.

Trained volunteers used AliveCor’s smartphone-based single-lead ECG to screen 10,735 Chinese adults (79.8 percent female/mean age 78.6 years) living in Hong Kong. All ECG’s were reviewed by cardiologists. Telephone follow-up on those identified with AFib was conducted three to nine months after screening.

Of those screened, 244 (2.3 percent) had AFib and newly diagnosed AFib was found in 30.3 percent (mean CHA2DS2VASc score of 3.9). Thirty-four (45.9 percent) of those newly diagnosed with AFib were asymptomatic. Study investigators noted the number-to-screen for one newly-diagnosed AFib was 145 and the prevalence of AFib increased by 43.5 percent using this Smartphone screening program. Follow up of AFib patients post screening showed 64.9 percent sought medical attention and 51.4 percent had been seen by a clinician. Additionally, 89.5 percent were indicated for oral anticoagulation, with 47.1 percent receiving oral anticoagulation appropriately and 44.1 percent maintaining excellent drug compliance.

“Although drug compliance in these citizens were satisfactory, the behavior of seeking medical attention and the prescription rate of oral anticoagulation was suboptimal,” study investigators said. They noted the effectiveness of a voluntary, community-led screening program is weakened by the lack of a structured downstream pathway that would provide newly diagnosed or undertreated AFib patients a way to receive appropriate oral anticoagulation therapy. They also suggested further evaluation of the cost-effectiveness of these types of programs both in China and other regions is needed.

In terms of the AliveCor device itself, the sensitivity and specificity of the device in diagnosing AFib was 76.8 percent and 99.6 percent respectively; while the positive predictive value was 83.2 percent and negative predictive value was 99.4 percent.

“The specificity and negative predictive value of the AliveCor diagnostic algorithm for AFib are excellent,” investigators said. “However the sensitivity is only fair.” They recommended further improvements to the sensitivity of the algorithm before it be used as a tool for auto-screening.