An apparatus comprising: an acquisition circuit configured and arranged to collect a first surface electrocardiography signal associated with a first location of a subject's heart and a second surface ECG signal associated with a second location of the subject's heart; preprocessing circuitry configured and arranged to perform detection and filtering of QRS complexes of the first surface ECG signal associated with the first location of the subject's heart and the second surface ECG signal associated with the second location of the subject's heart collected by the acquisition circuit; analysis circuitry configured and arranged to: from the first surface ECG signal associated with the first location of a subject's heart and the second surface ECG signal associated with the second location of the subject's heart, extract signal information comprising one or more of parameters and data points, segment the QRS complex of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex of the second surface ECG signal associated with the second location of the subject's heart using the extracted information, cross-correlate the QRS complex segment of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart to produce a correlation signal, and provide an asynchrony index that at least one of is based on and corresponds to the correlation signal between the QRS complex segment of the first surface ECG signal associated with the first location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart and that indicates a level of electrical asynchrony between the first location and the second location. an acquisition circuit configured and arranged to collect a first surface electrocardiography signal associated with a first location of a subject's heart and a second surface ECG signal associated with a second location of the subject's heart; preprocessing circuitry configured and arranged to perform detection and filtering of QRS complexes of the first surface ECG signal associated with the first location of the subject's heart and the second surface ECG signal associated with the second location of the subject's heart collected by the acquisition circuit; analysis circuitry configured and arranged to: from the first surface ECG signal associated with the first location of a subject's heart and the second surface ECG signal associated with the second location of the subject's heart, extract signal information comprising one or more of parameters and data points, segment the QRS complex of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex of the second surface ECG signal associated with the second location of the subject's heart using the extracted information, cross-correlate the QRS complex segment of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart to produce a correlation signal, and provide an asynchrony index that at least one of is based on and corresponds to the correlation signal between the QRS complex segment of the first surface ECG signal associated with the first location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart and that indicates a level of electrical asynchrony between the first location and the second location. from the first surface ECG signal associated with the first location of a subject's heart and the second surface ECG signal associated with the second location of the subject's heart, extract signal information comprising one or more of parameters and data points, segment the QRS complex of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex of the second surface ECG signal associated with the second location of the subject's heart using the extracted information, cross-correlate the QRS complex segment of the first surface ECG signal associated with the first signal location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart to produce a correlation signal, and provide an asynchrony index that at least one of is based on and corresponds to the correlation signal between the QRS complex segment of the first surface ECG signal associated with the first location of the subject's heart and the QRS complex segment of the second surface ECG signal associated with the second location of the subject's heart and that indicates a level of electrical asynchrony between the first location and the second location.