Validation of a Novel Smartphone-based Method for Heart Rhythm Monitoring in the Home Environment

Atrial fibrillation is a heart rhythm disorder with increased risk of stroke, heart failure, dementia and death. The severity of symptoms in atrial fibrillation varies markedly, ranging from no symptoms to those with disabling symptoms. An ECG recording is currently mandatory for diagnosing atrial fibrillation. A portable method for heart rhythm diagnostics that is readily available is currently missing in clinical practice. If a standard smartphone could be used for heart rhythm diagnostics, the availability could improve greatly. Treatment with direct current cardioversion is a procedure in which the heart rhythm is normalized by an electrical shock through the chest. Patients with atrial fibrillation are in some cases recommended treatment with direct current cardioversion but the procedure is costly, has a high recurrence rate and includes an increased risk for stroke. In this study we will validate the use of a novel smartphone-based method for heart rhythm diagnostics when used by patients in their home environment. The novel method is using the smartphone camera as a sensor. Patients will be doing heart rhythm measurements with the novel smartphone-based method in their home environment for 30 days after successfully receiving treatment of atrial fibrillation with direct current cardioversion. The novel smartphone-based method will be validated against simultaneous recordings with mobile ECG. We will also study the feasibility in using smartphone recordings and mobile ECG in the home environment the weeks before receiving treatment with direct current cardioversion, to study the possible benefit of detecting spontaneous conversions to normal heart rhythm and missed doses of treatment with blood thinning medication, both of which will lead to cancellation or detention of the cardioversion procedure.