STEMI Flashcards
What is a STEMI?
A STEMI (ST-Elevation Myocardial Infarction) is a type of acute coronary syndrome characterised by ST-segment elevation on ECG and myocardial necrosis.
What causes a STEMI?
It is caused by a complete occlusion of a coronary artery due to a ruptured atherosclerotic plaque and subsequent thrombus formation.
What are the common symptoms of a STEMI?
Severe chest pain (often crushing or squeezing), radiating to the left arm, neck, or jaw, dyspnoea, nausea, vomiting, and diaphoresis.
What are the risk factors for STEMI?
Smoking, hypertension, diabetes, hyperlipidaemia, obesity, sedentary lifestyle, and a family history of cardiovascular disease.
How is STEMI diagnosed?
Diagnosis is based on clinical presentation, ECG changes (ST elevation in two contiguous leads), and elevated cardiac biomarkers (e.g., troponin).
What are the characteristic ECG findings in STEMI?
ST-segment elevation in contiguous leads, new left bundle branch block (LBBB), or pathological Q waves.
What is the pathophysiology of STEMI?
Complete coronary artery occlusion leads to myocardial ischaemia and necrosis due to an imbalance between oxygen supply and demand.
What are the immediate management steps for a suspected STEMI?
ABCDE assessment, oxygen if hypoxic, aspirin, P2Y12 inhibitor (e.g., clopidogrel), nitrates, and consideration of reperfusion therapy.
What are the two main reperfusion therapies for STEMI?
Primary percutaneous coronary intervention (PCI) and thrombolysis.
What is primary PCI, and why is it preferred in STEMI?
PCI involves mechanically opening the occluded artery with a stent and is preferred because it has better outcomes compared to thrombolysis.
When is thrombolysis used in STEMI management?
Thrombolysis is used when PCI is not available within 120 minutes of first medical contact.
What medications are used during primary PCI?
Antiplatelets (aspirin, P2Y12 inhibitors) and anticoagulants (e.g., heparin) to reduce clot formation.
What is the role of beta-blockers in STEMI management?
Beta-blockers reduce myocardial oxygen demand by lowering heart rate and blood pressure, improving outcomes in certain patients.
What complications can arise from a STEMI?
Heart failure, arrhythmias (e.g., ventricular fibrillation), cardiogenic shock, ventricular rupture, and recurrent ischaemia.
What is the Killip classification in STEMI?
A system used to stratify the severity of heart failure in STEMI patients, ranging from no heart failure (Class I) to cardiogenic shock (Class IV).
What is the role of troponin in STEMI diagnosis?
Elevated troponin levels confirm myocardial necrosis and help differentiate STEMI from other causes of chest pain.
What lifestyle changes are recommended after a STEMI?
Smoking cessation, a heart-healthy diet, regular exercise, weight management, and adherence to prescribed medications.
What medications are part of long-term secondary prevention after a STEMI?
Dual antiplatelet therapy (aspirin and a P2Y12 inhibitor), statins, beta-blockers, ACE inhibitors, and possibly anticoagulants.
What is the role of statins in post-STEMI management?
Statins lower LDL cholesterol and stabilise atherosclerotic plaques, reducing the risk of recurrent events.
How is STEMI managed in patients with cardiogenic shock?
Management includes inotropic support (e.g., dobutamine), mechanical ventilation, and urgent PCI or coronary artery bypass grafting (CABG).
What are the ECG findings specific to an anterior STEMI?
ST elevation in leads V1-V4, often due to left anterior descending artery occlusion.
What are the ECG findings specific to an inferior STEMI?
ST elevation in leads II, III, and aVF, typically caused by right coronary artery occlusion.
Why is early recognition of a STEMI important?
Prompt diagnosis and reperfusion therapy minimise myocardial damage, reduce complications, and improve survival.
What are the indications for implantable cardioverter-defibrillator (ICD) post-STEMI?
ICDs are indicated in patients with reduced ejection fraction and high risk of ventricular arrhythmias.
