# Irregular Heartbeat ## Description Irregular heartbeats (IHB) are those that occur outside the user’s normal heart rhythm (e.g., a premature ventricular contraction). BitDoctor Technology can be used to detect and count the number of IHB the user experiences within a given measurement period. A bpm of 60-100 is considered healthy/normal. ## Method The ability to detect at least one irregular heartbeat via BitDoctor Technology was assessed against the presence of irregular heartbeats as determined by electrocardiograms (ECG) annotated by experienced cardiology nurses. ## Participants Subjects were recruited from several cardiology clinics. These patients had been referred for ECGs and a large proportion had irregular heartbeats. ## Additional Data Collection Setup Same as the [setup as HR](/clinical-measurement-reports/heart-rate.md#additional-data-collection-setup). ## Additional Data Collection Each 30-minute recording was then sub-divided into 1-minute samples, resulting in 12,000 1- minute samples. Some of these were excluded due to movement or poor signal quality, leaving 24 10,997 samples for analysis. The electrocardiograph for each sample was then annotated by a cardiology nurse to identify segments with IHB. ## Performance of IHB detection algorithm BitDoctor signal was extracted from each video and the IHB detection algorithm was employed to identify IHB within the signal. This algorithm employs machine-learning to identify IHB. The performance of this algorithm was assessed by recall, precision and f1 score. Recall is the percentage of cases where the BitDoctor-based algorithm detected an IHB when there was indeed an IHB (according to ECG). It was calculated as True Positives / (True Positives + False Negatives). Precision is the percentage of cases where an IHB actually occurred, out of all cases where the BitDoctor-based algorithm claimed an IHB had occurred. It was calculated as True Positives / (True Positives + False Positives). F1 score is the ‘harmonized mean’ of these measures, calculated as 2 \* (precision \* recall) / (precision + recall). ## Results Recall was 96%, precision was 82% and the F1 score was 89% in terms of detecting at least one IHB. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.bitdoctor.ai/clinical-measurement-reports/irregular-heartbeat.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.