1. Síndrome Coronario Agudo Flashcards
What is acute coronary syndrome (ACS)?
The clinical manifestation of myocardial infarct and commonly the default working diagnosis in patients with new-onset chest pain suspected to be of cardiac ischemic origin.
What is an infarction?
Tissue necrosis that results from insufficient blood and oxygen supply to the affected region. Etiologies include thromboembolic occlusion, rupture, vasoconstriction, and vessel compression.
What are the mainstays of the diagnosis of ACS?
- Clinical findings (onset and characteristics of pain, patient history)
- ECG
- Troponin
How are the patients classified based on ECG findings?
- With ST-elevation (STE-ACS)
- Non-ST-elevation ACS (NSTE-ACS).
What is a “ST elevation”?
An elevation of the ST segment above the isoelectric line.
Considered significant if it is ≥ 0.1 mV in a limb lead or ≥ 0.2 mV in a precordial lead.
What can be some of the causes of a ST elevation?
- Myocardial ischemia
- Pericarditis (diffuse ST elevations).
What is Troponin?
A group of muscle proteins found in skeletal and cardiac muscle that are involved in muscle contraction.
¿Para qué nos sirve la troponina en el contexto de un SCA?
In acute myocardial injury, troponins and other cardiac biomarkers are released into the blood.
Used as a highly sensitive and specific biomarker for cardiac muscle cell death (e.g., from myocardial ischemia in acute myocardial infarction).
What is Non-ST-elevation acute coronary syndrome (NSTE-ACS)?
An umbrella term for the entities NSTEMI and unstable angina (UA).
How are NSTE-ACS categorized?
Depending on serum levels of cardiac troponin (cTn):
- NSTEMI: positive myocardial injury biomarkers
- Unstable angina (UA): absence of detectable myocardial injury biomarkers
What do STE-ACS patients require immediately?
Revascularization therapy with percutaneous coronary intervention (PCI) or Fibrinolytic therapy.
What is revascularization therapy?
The restoration or augmentation of blood flow in a previously ischemic organ or body part (e.g., due to embolism or thrombotic occlusion).
Can be performed surgically (bypass surgery, endarterectomy, or surgical embolectomy) or through other interventions (percutaneous transluminal angioplasty or stenting, pharmacologic or mechanical thrombectomy/embolectomy).
What are some of the indications of thrombolytic therapy?
- STEMI
- Stroke
- Massive pulmonary embolism
- Severe deep vein thrombosis
- Acute limb ischemia
What are the two things all ACS patients receive?
- Dual antiplatelet therapy
- Anitially anticoagulation.
What is dual antiplatelet therapy?
Combination treatment with aspirin and a platelet P2Y12 receptor blocker (e.g., clopidogrel) used to reduce the risk of thrombosis after arterial stenting (e.g., PCI) and for secondary prevention of stroke.
What are the benefits of adjunctive therapy for ACS?
Beta blockers and oxygen can help reduce symptoms and have a positive impact on mortality.
What is acute coronary syndrome (ACS)?
The suspicion or confirmed presence of acute myocardial ischemia
Can subtypes of ACS be differentiated based on clinical presentation alone?
No
What is unstable angina?
Acute myocardial ischemia that is not severe enough to cause detectable quantities of myocardial injury biomarkers or ST-segment elevations on ECG
What is non-ST-segment elevation myocardial infarction (NSTEMI)?
Acute myocardial ischemia that is severe enough to cause detectable quantities of myocardial injury biomarkers but without ST-segment elevations on ECG
What is ST-segment elevation myocardial infarction (STEMI)?
Acute myocardial ischemia that is severe enough to cause ST-segment elevations on ECG
What are some of the symptoms of an acute myocardial infarction?
- Chest pain (Nonfocal retrosternal discomfort or pressure)
- Nausea
- Diaphoresis
- Lightheadedness
- Palpitations
- Dyspnea
What is the of athophysiology of unstable angina?
Partial occlusion of coronary vessel → decreased blood supply → ischemic symptoms without infarction
What is the of athophysiology of NSTEMI?
Classically due to partial occlusion of a coronary artery.
Affects the inner layer of the heart (subendocardial infarction)
What is the of athophysiology of STEMI?
Classically due to complete occlusion of a coronary artery.
Affects the full thickness of the myocardium (transmural infarction)