Cardiovascular - Summary Saunders Comprehensive Review for the NCLEX-RN Examination

Diagnostic Tests Cardiac Markers CK-MB (creatinine kinase, myocardial muscle) - an elevation in value indicates myocardial damage - an elevation occurs within hours and peaks at 18 hours following an acute ischemic attack Normal value male: 2-6ng/mL Normal value female: 2 to 5ng/mL Troponin Values are low, any rise can indicate myocardial cell damage - troponin I: rises within 3 hours and persists for up to 7-10 days (this one is especially related to myocardial injury) … less than 0.3ng/mL - troponin T less than 0.2ng/mL - serum levels of troponin T and I increase 4-6 hours after the onset of the MI, peak at 10-24 hours, and return to baseline after 10-14 days Myoglobin - myoglonin is an oxygen-binding protein found in cardiac and skeletal muscle - the level rises within 2 hours after cell death, with a rapid decline in the level after 7 hours - may not be cardiac specific Complete Blood Count (CBC) Red Blood Cell Count - decreases in rheumatic heart disease and infective endocarditis - increases in conditions characterized by inadequate tissue oxygenation White Blood Cell Count - increases in infectious and inflammatory diseases of the heart - increases after an MI because large numbers of WBCs are needed to dispose of the necrotic tissue resulting from the infarction