Systems and methods are provided for evaluating an expected effectiveness of cardiac resynchronization therapy. Electrocardiogram (ECG) data is received as at least one ECG lead from a set of electrodes. A frequency spectrum representing the ECG data is generated via a Fourier transform. At least one predictor value is extracted from the calculated frequency spectrum. A fitness parameter, representing the expected effectiveness of cardiac resynchronization, is determined from at least the extracted predictor value.