Prognostic value of Poincare´ plot indexes in chronic heart failure patients

The identification of prognostic indexes in chronic heart failure (CHF) patients represents a challenging task in the analysis of heart rate variability (HRV) We thus assessed the prognostic value of novel computer-generated quantitative descriptors of Poincare´ plots (PPlots) of HRV in a case-control study over 13 CHF patients who experienced cardiac death and 13 matched CHF controls. All subjects underwent Holter recording with computation of the standard deviation of normal-to-normal intervals (SDNN) and PPlot analysis. While visual classification of PPlots and SDNN did not significantly differentiate the controls from the deceased patients, a highly significant association with outcome was found for quantitative PPlot indexes. This preliminary study shows that automatic quantification of PPlots allows a better discrimination between patients at risk of cardiac events and controls than does a visual classification of plot features and time-domain HRV