Acute Myocardial Infarction with ST-Segment Elevation

Diagnosis and Initial Management

The European Society of Cardiology recommends immediate reperfusion therapy, with primary percutaneous coronary intervention (PCI) as the preferred method, and thrombolytic therapy if PCI is not available in a timely manner, within 12 hours of symptom onset 1, 2, 3
Record and interpret a 12-lead electrocardiogram (ECG) within 10 minutes of first medical contact to confirm the diagnosis of ST-segment elevation myocardial infarction (STEMI) 1, 3
Start ECG monitoring with defibrillation capability as soon as possible to identify life-threatening arrhythmias 1, 4
Record right precordial leads (V3R and V4R) in all patients with inferior STEMI to detect concomitant right ventricular infarction 1, 4

The European Society of Cardiology recommends reperfusion therapy for all patients with symptoms of ischemia lasting less than 12 hours and persistent ST-segment elevation 2, 3, 5
Patients should be taken directly to the catheterization laboratory, bypassing the emergency department 2, 3
Administer a potent P2Y12 inhibitor (ticagrelor, prasugrel, or clopidogrel) before or during PCI, in addition to aspirin 2, 3, 5, 6
Aspirin should be administered orally or intravenously as soon as possible 2, 3, 5, 6

If primary PCI is not available in a timely manner, start fibrinolytic therapy within 12 hours of symptom onset in the absence of contraindications 2, 3, 5
Prefer fibrin-specific agents (tenecteplase, alteplase, or reteplase) 2, 3, 5, 6
Initiate thrombolysis as early as possible after diagnosis of STEMI, preferably at the prehospital stage 2, 3, 5, 6

Transfer patients to a PCI-capable center immediately after thrombolysis 2, 3, 5, 6
Perform emergency angiography and PCI for cardiac failure or shock 2, 3, 5, 6
Rescue PCI should be performed immediately in cases of failed thrombolysis (less than 50% reduction in ST-segment elevation at 60-90 minutes) or hemodynamic or electrical instability 2, 3, 5, 6
Angiography and PCI of the infarct-related artery should be performed within 2-24 hours after successful thrombolysis 2, 3, 5, 6

Dual antiplatelet therapy (aspirin plus ticagrelor, prasugrel, or clopidogrel) for 12 months after PCI 2, 5, 6
Beta-blockers in patients with heart failure and/or left ventricular ejection fraction less than 40% 5, 6
Angiotensin-converting enzyme (ACE) inhibitors within the first 24 hours in patients with heart failure, left ventricular dysfunction, diabetes, or anterior infarction 5, 6
High-intensity statin therapy as soon as possible, with a target low-density lipoprotein cholesterol level of less than 1.8 mmol/L 5, 6
Proton pump inhibitors in patients at high risk of gastrointestinal bleeding 5, 6

Avoid intravenous beta-blockers in patients with hypotension, acute heart failure, AV block, or marked bradycardia 5, 6
Routine oxygen therapy is not recommended in patients with oxygen saturation greater than or equal to 90% 3
Fondaparinux is not recommended for primary PCI 2, 5, 6

Development of acute heart failure after fibrinolysis is an indication for immediate rescue percutaneous coronary intervention (PCI). American College of Cardiology/American Heart Association (ACC/AHA) guideline – Class I, Level A. 7

Aspirin 81 mg daily should be continued indefinitely when a loading dose has already been administered. ACC/AHA guideline – Class I, Level A. 7

Initiate oral beta‑blockers within the first 24 hours in all STEMI patients without contraindications (e.g., hypotension, acute heart failure, high‑grade AV block, marked bradycardia). ACC/AHA guideline – Class I, Level A. 7

Start an ACE inhibitor (or an ARB if ACE‑inhibitor intolerant) within the first 24 hours in patients with any of the following: anterior MI, clinical or radiographic signs of heart failure, left‑ventricular ejection fraction ≤ 40 %, diabetes mellitus, or hypertension. ACC/AHA guideline – Class I, Level A. 7

Begin high‑intensity statin therapy as early as possible during the hospital stay, aiming for an LDL‑cholesterol target < 1.8 mmol/L (< 70 mg/dL). ACC/AHA guideline – Class I, Level A. 8

Perform a transthoracic echocardiogram during hospitalization to determine left‑ventricular ejection fraction and overall ventricular function; patients with LVEF < 40 % should receive intensified medical therapy (beta‑blocker, ACE‑I/ARB). ACC/AHA guideline – Class I, Level A. 7

Provide smoking‑cessation counseling to every hospitalized smoker and document the intervention in the medical record. ACC/AHA guideline – Class I, Level A. 8