ABPM-FIT and CV-SORT: an easy-to-use software package for detailed analysis of data from ambulatory blood pressure monitoring.

We describe a non-profit software package for the computerized analysis of ambulatory blood pressure monitoring (ABPM) recordings, in order to make it available to researchers in cardiovascular physiology, pharmacology and medicine. The first program, ABPM-FIT, can load data from several ABPM devices directly as they are stored on disk, making complicated data conversion steps unnecessary. The program performs conventional linear analyses of ABPM data automatically by calculation of mean, SD, load (the percentage of data above a chosen limit), and highest and lowest readings in user-defisned day and night periods. In addition, the area under the parameter-time curve (AUC) and the weighted mean (AUC/time) is calculated for all parameters monitored. In a second step, ABPM-FIT performs a rhythm analysis by fitting partial Fourier series to the data. Only those hormonics are included which significantly reduce the residual variance of the fit. The parameters of these functions (mesor, amplitudes, acrophases), values derived from the composed curves (maximum and minimum, AUC) and their slopes (e.g. maximal increase and decrease) are calculated automatically and, if desired, saved on disk. The second program, CV-SORT, loads groups of result files saved by ABPM-FIT, allows the extraction of parameters of interest for further analyses and creates spreadsheets containing the selected values from groups of patients. In addition, CV-SORT performs simple statistics, and calculates group mean circadian blood pressure and heart rate profiles from individual Fourier curves, with SD, confidence intervals or percentiles. The features of both programs are shown in exemplary analyses of ABPM recordings.