Sentence:  Or ( more commonly , thinks Keys ) the deposits themselves get so big that they choke off the artery 's flow to the point that an infarct occurs : the heart muscle is suffocated , cells supplied by the artery <WSD>die</WSD> , and the heart is permanently , perhaps fatally injured . 
Meaning of the word marked with <WSD> tags:  pass from physical life and lose all bodily attributes and functions necessary to sustain life