Slope of autocorrelation function of detrended 24-hour RR-intervals independently predicts mortality in postinfarction patients

Although Heart Rate VariabiliQ (HRV) was shown to be associated with mortulity of post myocardial infurction (Mi) patients, the clinical use of conventional HRV parameters is limited. We proposed new method based on the analysis of autocorrelation function (ACF) of detrended RR interval recordings. One thousand four hundred f f r y five consecutive post MI patients were enrolled into the prospective blinded study at German Heart Center in Munich. The RR intervals were extracted from 24 k Holter recordings using integrated sojiwure. The linear trend was estimated and subtracted from RR recordings. The ACF(m) was calculated for original and detrended RR-intervals. The slope (AS) of regression line fitted for ACF (m; m=I.IO) was dichotomized ut AS=-O.0025. AS >-0.0025 was considered as pathological. The signijkant association of pathological AS was revealed in univariate analysis (Log Rank =39.19, p\n\n\t\t