RESUMO
BACKGROUND: Mobile electrocardiograms (mECGs) utilizing smartphone applications are an emerging technology. Typically, a Lead I rhythm strip is recorded. However, interpretation can be difficult in patients with sinus rhythm and low amplitude P-waves (SR-LAP) or atrial flutter (AFL). We hypothesized that patients could independently obtain multi-lead tracings using a commercial mECG device, and that cardiologists who interpreted the multi-lead tracings would make more accurate diagnoses and have more confidence in their interpretation compared to a single lead only. METHODS: Thirty sets of recordings were obtained from 10 patients with either SR-LAP or AFL that was not apparent on Lead I on a standard ECG. Patients recorded Lead I, Lead II, and Lead V1 tracings using AliveCor's KardiaMobile mECG device. Twenty-nine cardiologists reviewed each patient's Lead I tracing, multi-lead tracings (Leads I, II, V1), and 12-lead ECG. Accuracy was noted and each cardiologist rated their level of confidence in their interpretation. RESULTS: All patients were able to record their own single and multi-lead tracings. Single lead, multi-lead, and the 12-lead ECG yielded 36.4%, 84.3%, and 97.7% agreement with the established diagnosis, respectively (P < .01 for each comparison). Overall mean confidence scores (out of a score of 5) were 2.95, 3.50, and 4.47 for single lead, multi-lead, and the 12-lead ECG, respectively (P < .01 for each comparison). CONCLUSIONS: Patients were able to record their own multi-lead mECG tracings. Compared to a single lead recording, multi-lead mECGs significantly improved cardiologists' diagnostic accuracy and confidence in their interpretation approaching that of a standard 12-lead ECG.