The document discusses guidelines for the appropriate use of cardiac resynchronization therapy (CRT) according to the ACCF/HRS/AHA/ASE/HFSA/SCAI/SCCT/SCM2013 criteria. CRT is assigned a score between 1 and 9, with 7-9 indicating appropriate use, 4-6 indicating may be appropriate, and 1-3 indicating rare appropriate use. The document provides the criteria scores for various patient conditions and indications for CRT.