Heart monitor for detecting ectopic beats in an input electrocardiogram signal that includes an electrocardiogram signal input and a morphological signal analyzer connected to the electrocardiogram signal input, the analyzer being adapted to generate a first time series of values representing the input electrocardiogram signal, a second signal analyzer adapted to generate generating a modified time series of values representing a trend of values of the first time series and a comparison stage being adapted to compare the first time series with the modified time series to thus detect ectopic beats. The invention further relates to a method for detecting ectopic beats in an input electrocardiogram signal that includes obtaining an electrocardiogram signal, generating from the electrocardiogram signal a first time series of values representing the input electrocardiogram signal, generating a modified time series of values representing a trend of values of the first time series and comparing the first time series with the modified time series to thus detect ectopic beats.