CRTD Biventricular

In heart failure patients CRT, or biventricular pacing, is used to help improve the heart's pumping function and the symptoms associated with the arrhythmia. 

CRT implant procedure involves matchbox sized pacemaker, usually kept just below the collarbone. Three wires (leads) are connected to the device to emit tiny electrical impulses which are set to resynchronize the heart. 

CRT therapy combined with a defibrillator backup is called CRT-D.