1. A system for determining a cardiac condition of a subject, the monitoring system comprising: one or more electrodes configured to sense a cardiac activity of a subject; and a processor configured to: i. receive ECG signals acquired using the one or more electrodes; ii. analyze the ECG signals to delineate cardiac waveforms on a beat-to-beat basis; iii. identify, in the delineated cardiac waveforms, characteristic points associated with different phases of cardiac activity; iv. for each delineated cardiac waveform, compute an ischemic index using a combination of ECG signals corresponding to a ventricular depolarization period and a ventricular repolarization period, wherein the ventricular depolarization period and the ventricular repolarization period are defined by the characteristic points identified in step iii) and at least one ischemic index is computed by taking a ratio between an ST height and an amplitude of a QR segment; v. determine a cardiac condition of the subject using at least one ischemic index computed; vi. generate a report indicative of the cardiac condition of the subject.