a transceiver receiving signals, in at least one of a wireless manner and a wired manner, the signals representing a plurality of electrocardiogram (ECG) data from a plurality of ECG leads applied to a patient, the ECG data corresponding to a coronary artery set, the transceiver configured to at least one of filter and amplify the signals;

a storage medium storing a plurality of modules; and

a processor coupled to the storage medium and the transceiver and accessing and executing the plurality of the modules, wherein the plurality of the modules comprise:

a first prediction module, wherein according to the plurality of the electrocardiogram data and at least one first phase model, at least one first probability vector corresponding to the at least one first phase model is generated, a first determined result is generated according to the at least one first probability vector, and in response to each one in a first subset of the at least one first probability vector being greater than a first threshold, a first data subset corresponding to the first subset from the plurality of the electrocardiogram data is selected, wherein the first determined result indicates a probability of a blockage of the coronary artery set, wherein the at least one first phase model and the at least one second phase model correspond to a machine learning algorithm executed by the processor, wherein the first determined result is determined according to a first product of at least one first average element value corresponding to the at least one first probability vector and at least one first weight, wherein the at least one first weight is associated with a performance index of the at least one first phase model;

a second prediction module, wherein according to the first data subset and at least one second phase model, at least one second probability vector corresponding to the at least one second phase model is generated, and a second determined result is generated according to the at least one second probability vector, wherein the second determined result indicates a probability of a blockage of a first coronary artery in the coronary artery set, wherein the first coronary artery comprises at least one of a left main coronary artery, a left anterior descending (LAD) artery, a left circumflex (LCX) artery, and a right coronary artery; and

an output module outputting the first determined result and the second determined result through the transceiver.