Detecting symptomatic heart rhythms in the Emergency Department


The AliveCor Heart Monitor was able to detect symptomatic heart rhythms at a higher rate than by standard care alone among patients who presented to the Emergency Department with palpitations and pre-syncope.

In patients who present to the Emergency Department (ED) with palpitations and pre-syncope, diagnosis of the underlying heart rhythm is challenging. This is because the patients fully recover by the time they are seen in the ED. Moreover, due to the infrequency of symptoms in these patients, conventional 12-lead ECG investigations and ambulatory monitoring have limited diagnostic efficacy.

This study published in The Lancet showed the potential of smartphone-based ECG recorders, like AliveCor’s KardiaMobile, in capturing patients’ ECG readings during symptoms.

This randomized controlled trial, conducted at 10 hospitals in the UK recruited participants who presented with palpitations and pre-syncope to the ED and had undiagnosed ECG rhythms upon ED assessment. Those in the intervention group received an AliveCor heart monitor in addition to the standard care.  Participants in the intervention group were able to record an ECG in the AliveCor Heart Monitor and email this ECG at any time to the research team. All participants were followed up at 90 days.

The trial results reported:

  • Heart rhythms during symptoms were detected in 55.6% (95% CI: 46.9 – 64.4%) of the participants in the intervention group compared to only 9.5% (95% CI: 4.2 – 14.8%) of those in the control group.
  • The mean time to symptomatic rhythm detection was lower in the intervention group (9.5 days; SD, 16.1; range, 0–83) compared to the control group (42.5 days; SD, 16.0; range, 12–66).
  • The most common symptomatic heart rhythms detected in the intervention group included: sinus rhythm (66% of the participants), sinus tachycardia (17% of the participants), ectopics (12% of participants), and atrial fibrillation (12% of the participants).

Conclusion: The five-fold increase in the symptom-rhythm correlation when using AliveCor’s heart monitor shows that such smartphone-based ECG monitors can significantly improve patient care and clinical assessment. The use of AliverCor’s non-invasive, convenient ECG device should be considered in the on-going care for all patients presenting acutely with unexplained palpitations or pre-syncope.