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ULY CLINIC
ULY CLINIC
14 Aprili 2025, 11:33:56
ST Elevation Myocardial Infarction (STEMI) /Acute Myocardial Infarction (AMI)
STEMI/AMI is a medical emergency caused by the complete or partial occlusion of a coronary artery and requires prompt hospitalization and intensive care intervention management.
Signs and symptoms
Severe chest pain with the following characteristics, site: retrosternal or epigastric, quality: crushing, constricting or burning pain or discomfort, radiation: to the neck and/or down the inner part of the left arm, duration: at least 20 minutes and often not responding to sublingual nitrates, occurrence: at rest. May be associated with: pulmonary oedema sweating, hypotension or hypertension, arrhythmias
Diagnostic criteria
Initial diagnosis:
Management including both diagnosis and treatment of STEMI/AMI starts at the point of first medical contact (FMC), defined as the point at which the patient is either initially assessed by a paramedic or physician or other medical personnel in the pre-hospital setting, or the patient arrives at the hospital emergency department.
Simple recognition triage: Two out of three points most likely point to STEMI/AMI diagnosis
Symptoms - typical/atypical chest pain
ECG – ST elevation in in two contiguous leads≥0.1mV
Raised cardiac biomakers– Total Creatine Kinase (Total-CK), Creatine Kinase MB (CK-MB) and Standard/High Sensitive Troponin I or T
Control cardiac pain
Glyceryl trinitrate sub-lingual/ spray 0.5mg (make sure patient hasn’t taken phosphodiesterase-5 inhibitor). For persistent pain and if oral therapy is insufficient
Glyceryl Trinitrate IV, 1–2 µg/kg/min titrated with chest pain over 8–24 hours.
OR
Morphine, IV, 1–2 mg/minute dilute 10 mg up to 10 mL with sodium chloride solution 0.9%. Total maximum dose: 10 mg, repeat after 4 hours if necessary.
Anti-platelets therapy
Aspirin 300mg stat (O) then followed by 75mg/100mg daily
Plus
Clopidogrel 300mg/600mg stat then followed by 75mg daily next day
Statin high dose
Simvastatin 80mg stat then 40mg daily
OR
Atorvastatin 80mg stat then 40mg daily
OR
Rosiivastatin 10mg-40mg daily
Anticoagulant
Heparin UFH 70–100U/Kg body weight IV a day
OR
Enoxaparin 1mg/kg body weight sc bid, Reduce dose in renal failure patient to 0.5mg/kg
Beta blocker (ß –blockers)
In case of LV dysfunction
Carvedilol initial dose 6.25mg twice daily preferred, titrate dose upward to maximum dose 25mg twice daily In the settings of normal systolic function
Atenolol 12.5mg or 25mg or 50mg once a day,
OR
Metoprolol 25m/ or 50mg once a day
Angiotensin-Converting Enzyme Inhibitors (ACEIs)
Captopril 6.25mg or 12.5mg (PO) 8 hourly
OR
Enalapril 10mg twice a day
OR
Perindopril 4mg/8mg (PO) daily
Definitive management of STEMI – Reperfusion therapy (Myocardial reperfusion)
Myocardial reperfusion with rapid recanalization of infarct related artery is the key to success in the management of ST Elevation Myocardial Infarction (STEMI).
Timely reperfusion is crucial for minimization of infarct size and thereby for preservation of left ventricular function and reduction in mortality in STEMI patients
The two main reperfusion strategies for STEMI patients are;
Thrombolytic/Fibrinolytic therapy) and
Primary percutaneous coronary intervention (PPCI)
Thrombolytic agents
Streptokinase IV, 1.5 million units diluted in 100 mL sodium chloride 0.9%, infused over 30–60 min
OR
Alteplase (TPA) 15mg as bolus, 0.75mg/kg over 30min, then 0.5mg/kg over 60min
OR
Tenecteplase 40mg IV bolus (70–79kg body weight) 30 –35mg < 70kg body
Absolute contraindication for thrombolytic
Previous allergy to streptokinase or used within the last year for streptokinase only
Stroke CVA within the last 3 months
History of recent major trauma
Bleeding within the last month
Aneurysms
Brain or spinal surgery or head injury within the preceding month
Active bleeding or known bleeding disorder
Relative contraindication for Thrombolytic
Refractory hypertension
TIA in the preceding 6 months,
Subclavian central venous catheter
Warfarin therapy
Pregnancy
Traumatic resuscitation
Recent retinal laser treatment
Referral is urgent for all suspected or diagnosed cases to high level care equipped with cardiac catheterization laboratory.
Non pharmacological
Supportive therapy
Consider cardio-pulmonary resuscitation if necessary before transfer (cardiac arrest– cardiopulmonary resuscitation).
Oxygen 40% via facemask, if saturation < 92% or if in distress
See section 20.4.1 above on supportive therapy for NSTEMI