Tissue necrosis in STEMI heart attack typically affects A. whole thickness of myocardium B. papillary muscles only C. parietal pericardium only D. endocardium only E. visceral pericardium only Tissue necrosis in STEMI heart attack typically affects A. whole thickness of myocardium B. papillary muscles only C. parietal pericardium only D. endocardium only E. visceral pericardium only.