Various embodiments include methods of cardiac resynchronization therapy (CRT). Various embodiments may include: generating, using a processing unit, a cardiac activation map including a three-dimensional (3D) heart model of the heart that shows coronary vessels of a patient and shows the propagation of electrical signals through the 3D heart model； determining the location of a left bundle branch block (LBBB) based on the cardiac activation map； implanting a first pacing device and a second pacing device into the patient； stimulating the His Bundle of the heart using the first pacing device； and stimulating the left ventricle (LV) of the heart at a position downstream of the LBBB with respect to a direction of electrical conduction through the LV using the second pacing device after stimulating the His bundle.
