METHOD AND APPARATUS FOR PRODUCING INFORMATION INDICATIVE OF CARDIAC MALFUNCTIONS

An apparatus for producing information indicative of cardiac malfunctions, for example atrial fibrillation, includes a processing system for processing an analysis signal produced by a sensor system responsive to motion including cardiovascular motion. The processing system is configured to form a first indicator quantity indicating degree of concentration of the autocorrelation of the analysis signal to a point corresponding to zero time difference between analysis signal samples whose mutual correlation is expressed by the autocorrelation and a second indicator quantity indicating the spectral entropy of the analysis signal. The processing system is configured to determine an indicator of cardiac malfunction on the basis of at least the first indicator quantity and the second indicator quantity.