Acute coronary syndrome (updated) questions with correct answers

Types of acute coronary syndrome (ACS) - Answer ST-elevation ACS: acute chest pain and persistent (>20 mins) ST-segment elevation. Most develop ST-elevation myocardial infarction (STEMI). Non-ST-elevation ACS: acute chest pain without persistent ST-segment elevation. - unstable angina: normal troponin levels as no necrosis (although occasionally there can be minor rises in troponin signifying increased risk of subsequent cardiac events). - non-ST-elevation myocardial infarction (NSTEMI): rise in troponin Physiologically what causes the difference between a STEMI and an NSTEMI - Answer STEMI - transmural infarct (affects all of myocardia wall) NSTEMI - subendocardial infarct (necrosis <50% of myocardial wall) What is the most common cause of ACS? - Answer Atheromatous plaque in coronary artery with platelet rich thrombus Non-thrombotic causes of ACS? - Answer Increased myocardial O2 demand (thyrotoxicosis, high cardiac output) Reduced oxygen delivery (anaemia, hypoxia) Coronary spasm (cocaine use, phaeochromocytoma, Prinzmetal's angina) Coronary artery dissection