Criteria for short QT interval based on a new QT-heart rate adjustment formula
نویسنده
چکیده
BACKGROUND A short QT interval, within which an increased risk for atrial fibrillation and/or fatal cardiac arrhythmias occurs, has been difficult to define. METHODS The lower percentiles of a new QTc formula were determined, using a precise mathematical fitting of the QT-heart rate relationship from the ECGs of 13,600 individuals from the NHANES II and III surveys. RESULTS The QTc interval for persons in the lower fifth percentile, second (2.5th) percentile and first percentile, were calculated. CONCLUSIONS Based on the new spline formula, a short QTc is defined at the first percentile, and is less than 380 ms in both men and women.
منابع مشابه
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