Usefulness of a Single-lead Electrocardiographic Recording System and Wireless Transmission During the COVID-19 Pandemic

Background: Some therapies used for COVID-19 can prolong the QT interval and produce severe arrhythmias. QT interval measuredfrom a standard electrocardiogram (ECG) requires additional personnel and risk of infection. Novel technologies to obtain anECG connected to smartphones provide an alternative for the evaluation of corrected QT interval (QTc).Objective: The aim of this study was to evaluate the feasibility of using a single-lead ECG device to measure the QT interval in patientswith suspected or confirmed COVID-19 before receiving treatment with drugs that can prolong the QT interval.Methods: The ECG was obtained with a KardiaMobile (KM) device and transmitted to a smartphone. The ECG recordings weresaved as pdf files and electronically submitted to the electrophysiology section which centralized the reception and assessed themeasured QT and QTc intervals.Results: A total of 31 patients (mean age 61 years, range 20-95 years) with suspected COVID-19 enrolled for treatment with hydroxychloroquine,azithromycin, ritonavir or lopinavir were analyzed. The recordings could be read in all the cases and had to be repeatedin two cases. The mean value of the QTc interval was 423 ms (range 380-457 ms) in men and 439 ms (range 391-540 ms) in women.The response time since the ECG recording was submitted for analysis was 11 min (range 1-155).Conclusions: The QTc interval could be measured from ECG recordings obtained with KM devices connected to a smartphone andtransmitted to a centralized reading center in all patients.