| 摘要 |
The presence of irregular heartbeat and/or possible atrial fibrillation is determined by analyzing a measured pulse rate pattern or heart rate pattern. The standard deviation and mean of time intervals each corresponding to a respective heartbeat are determined and compared to a threshold value. When quotient formed by dividing the standard deviation by the mean has a value greater than or equal to the threshold value, the shortest one of the time intervals and its succeeding time intervals are determined, and the succeeding time interval is compared to the mean. If the succeeding time interval is less than the mean, then the heartbeat is irregular. Alternatively, if the succeeding time interval is greater than the mean, the shortest time interval and its succeeding time interval are eliminated from the sample values, a new mean and standard deviation are determined, and the quotient of the new standard deviation divided by the new mean are compared to the threshold value. When the quotient is greater than the threshold value, the next shortest interval is determined, and the absolute value of the difference between the next shortest interval and the shortest interval is compared to an empirically determined value. If the difference is greater than the empirically determined value, the heartbeat is irregular. Alternatively, if the difference is greater than the empirically determined value, then the next shortest interval and its succeeding interval are redefined as the new shortest interval and is succeeding interval. The steps are repeated until it is determined that the heartbeat is regular or irregular.
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