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Prospective, multicentre validation of a simple, patient-operated electrocardiographic system for the detection of arrhythmias and electrocardiographic changes.

AIMS
Electrocardiographic changes, e.g. arrhythmias causing syncope or palpitations, are often transient and therefore difficult to diagnose. Systematic and symptom-activated ECG recordings can increase diagnostic yield in such patients. We evaluated the diagnostic accuracy of a simple, leadless, patient-operated ECG device compared with a standard 12-lead ECG.


METHODS AND RESULTS
We recorded a standard 12-lead surface ECG and a patient-activated ECG in direct succession in 508 consecutive patients enrolled in four centres. All ECGs were analysed by a single, blinded observer. ECGs were analysable in 505 (99.4%) patients (66% male, age 61 +/- 15 years, and body mass index 27 +/- 4). Analysis of the patient-activated ECG adequately detected a normal ECG (sensitivity 91% and specificity 95%), atrial fibrillation (AF) (sensitivity 99% and specificity 96%), and even T-wave abnormalities (sensitivity 90% and specificity 75%). Diagnostic accuracy for atrioventricular nodal block was moderate (sensitivity 79% and specificity 99%). Continuous parameters correlated well: (r(2) = 0.89 for heart rate, 0.83 for PR interval, 0.78 for QRS duration, and 0.89 for QTc).


CONCLUSION
Recordings made by this patient-operated ECG device allow to detect arrhythmias and other ECG changes with high accuracy compared with a standard ECG. It may help to improve accurate diagnosis of transient ECG changes such as paroxysmal AF in palpitations or other unexplained cardiac symptoms.