Acute Coronary Syndromes + Acute myocardial Infarction : Presentation & Management Flashcards
<p>What are the different incidences of caridac chest pain?</p>
<p>New excertional angina?</p>
<p>Unstable angina?</p>
<p>Acute MI?</p>
<p>Sudden Cardiac Death?</p>
<p>New exertional angina - 52%</p>
<p>Unstable angina - 13%</p>
<p>Acute MI - 22%</p>
<p>Sudden cardiac death - 13%</p>
<p>What is Stable Angina defined as?</p>
<p>Myocardial blood flow does not meet demand - ischaemia</p>
<p></p>
<p>Central chest tightness, often radiation to neck and/ or arms.</p>
<p>Aggravated by exertion & stress.</p>
<p>Relief by stopping activity & rapid improvement with sublingual nitrate.</p>
<p>What are the different acute coronary syndromes?</p>
<p>Unstable angina</p>
<p>NSTEMI- Non-ST-segment elevation MI</p>
<p>STEMI</p>
<p>How does atherothrombosis formation (the pathogenesis of all acute coronary syndromes) occur?</p>
<p>Plaque disruption</p>
<p>Why do plaques rupture?</p>
<p>Inflammation and sheer stress</p>
<p>What is the main difference between acute coronary syndromes and ACS?</p>
<p>ACS symptoms will almost always give symptoms at rest in contrast to stable angina which is only on exertion.</p>
<p>What are the non-modifiable risk factors for Acute Coronary Syndromes?</p>
<p>Age, gender, creed, family history & genetic factors.</p>
<p>Previous angina, cardiac events or interventions.</p>
<p>What are the modifiable risk factors for Acute Coronary Syndromes?</p>
<p>Smoking</p>
<p>Diabetes mellitus</p>
<p>Hyperlipidaemia</p>
<p>Hypertension</p>
<p>Lifestyle- exercise & diet</p>
<p>What is a typical history of unstable angina Pectoris (UAP)?</p>
<p>Angina on effort</p>
<p>Progressive increasing severity and frequency</p>
<p>Often provoked by less exertion and/or then at rest</p>
<p>What is a typical history for those with NSTEMI?</p>
<div>More often start with myocardial ischaemic symptoms occurring at rest.</div>
<p>What is the pain like in acute coronary syndromes?</p>
<p></p>
<p>Site - retrosternal</p>
<p>Character -often tight band/pressure/heaviness</p>
<p>Radiation -neck and/or into jaw, down arms</p>
<p>Aggravating factors -with exertion, emotional stress</p>
<p>Relieving factors:relieving factors e.g. incomplete improvement with GTN, or physical rest; and/or ongoing</p>
<p>What must you ensure to check for on <u>examination</u> for unstable angina and NSTEMI?</p>
<p>HR, BP</p>
<p>Listen for murmurs, crackles in chest</p>
<p></p>
<p>May look very unwell</p>
<p>May look completely fine</p>
<p>Often no specific features to find</p>
<p>What are the possible investigations for unstable angina and NSTEMI?</p>
<p>Electrocardiogram and Biomarkers</p>
<p>What are common results of ECG in UAP and NSTEMI?</p>
<p>Often normal ECG results</p>
<p>Commonly ST-segment depression, transient ST-segment elevation and/or T-wave inversion</p>
<p>More often in UAP changes resolve after pain, and in NSTEMI they tend to persist (but not always);</p>
<p>serial ECGs to detect delayed changes essential</p>
<p>Why is the difference in infarction between STEMI and NSTEMI?</p>
<p>STEMI - transmural</p>
<p>NSTEMI - sub endocardial infarct</p>
<p>How do you differentiate between NSTEMI and unstable angina?</p>
<p>Biomarkers - troponin and CKMB</p>
<p></p>
<p>Here is why there is a rise in ST segment in STEMI</p>
<p>Rise in ST segment because:</p>
<p>Infarcted tissue loses the ability to maintain resting potential of -90mv. Sodium potassium pumps no longer work, so it is partially depolarised. Normally true baseline of an ECG is zero because there is no difference in voltage. However the positve vector of depolarisation travels away from the electrode - negative deflection of baseline – so it shifts lower. ST segment now appears elevated because the ST segment is where there is complete depolarisation – so the ST segment is on the true baseline. In comparison to original baseline, ST segment is higher up.</p>
<p>Here is why there is ST depression in NSTEMI</p>
<p>NSTEMI – depolarisation vector travels towards the detector, shift of baseline upwards. ST segment refers to the point where there is complete depolarisation. ST segmentnow appears lower. ST segment returns to normal because of fibrosis. Fibrotic tissue doesn’t have the ionic leakage of necrotic tissue.</p>
<p>When is there likely going to be an atypical ACS presentation?</p>
<p>In women; the elderly or diabetics, influenced by reduced pain sensation.</p>
<p>What are the symptoms of angina and NSTEMI?</p>
<div>Breathlessness alone +/- signs of heart failure</div>
<div>Nausea & vomiting +/- other autonomic symptoms</div>
<div>Epigastric pain +/- recent onset indigestion</div>
<p>What does elevated cTn (cardiac troponin) suggest?</p>
<p>High risk of adverse events</p>
<p></p>
<p>Beware, not all troponin elevations are a ACS and caused by atherothrombosis</p>
<p>What does elevation of cardiac troponin indicate?</p>
<p>Elevated with compromise of myocyte integrity.</p>
<p>Sensitive and specific marker of cardiac myocyte damage</p>
<p>What do the levels of biomarkers indicate?</p>
<p>Characteristic rise and fall of cTn with ischaemic damage</p>
<p>Different pattern for acute myocardial infarction to unstable angina pectoris</p>
<p>What is the immediate treatment for UAP and NSTEMI?</p>
<p>First ABCDE approach, then MONA</p>
<p>Morphine (or diamorphine)</p>
<p>Oxygen</p>
<p>Nitroglycerine (GTN spray or tablet)</p>
<p>Aspirin 300 mg orally (crush/chew)</p>