⇒ . Cardiac Enzymes (intracellular enzymes leak out of infarcted myocardium) CK – peaks at 24h. Also produced by skeletal muscle + brain therefore request myocardium-bound fraction (CK-MB) which is specific for myocardial damage. Serum level of the enzyme relates to site of infarct Troponin – most reliable 12h post event. Highly specific (proteins involved in muscle contraction). Remain elevated for weeks therefore use CK to assess infarction in pt whose trop remains high from previous MI 2. ECG Hyperacute changes = tall, pointed T-waves followed by ST elevation. This is followed by T wave inversion. R wave voltage then decreases and Q waves develop Weeks – months = T wave may become upright again, Q waves remain. Inferior MI – involves leads II, III and aVF Anterior MI – affects precordial leads Anteroseptal MI – affects leads V1-V3 Lateral MI – affects leads I and aVL and V5-V6 Posterior MI – tall R wave in V1 and V2 with ST depression and upright T waves Note that there may be reciprocal ST-depression in leads opposite the site of infarction Development of new LBBB is an indicator of acute MI. However, it is a common abnormality – look at old ECGs Management - Emergency Care o Aspirin 300mg PO o Pain-relief 5-10mg morphine + metoclopramide (anti-emetic).