Further Management of STEMI
Activate the cardiac catheterization laboratory immediately and proceed with primary percutaneous coronary intervention (PCI) without waiting for troponin results—the ECG showing significant ST-elevation with ischemic symptoms is sufficient for diagnosis and demands emergent reperfusion therapy. 1
Immediate Actions Required (Within Minutes)
Dual antiplatelet therapy:
- Administer aspirin 160-325 mg chewed immediately 1, 2
- Add P2Y12 inhibitor: ticagrelor 180 mg or prasugrel 60 mg (if no contraindications such as prior stroke or age >75 years) 1, 2
Pain management and supportive care:
- Provide morphine titrated intravenously for pain relief and to reduce sympathetic activation 1
- Administer oxygen supplementation only if saturation is <90%—routine oxygen is not indicated 1
- Establish continuous ECG monitoring with defibrillation capability for potentially fatal arrhythmias 1, 2
Do not delay reperfusion for troponin results: The combination of typical ischemic chest pain lasting hours plus significant anteroseptal ST-elevation on ECG is diagnostic for acute proximal LAD occlusion requiring immediate catheterization 1
Primary PCI Strategy
Target door-to-balloon time <90 minutes 1, 2
During the index PCI procedure:
- Treat the culprit lesion (proximal LAD) first 2
- If clinically safe and indicated, treat any high-grade disease in non-infarct related arteries during the same procedure to minimize repeat exposures and optimize outcomes 2
Radial access is preferred over femoral access to reduce bleeding complications 2
High-Risk Features in This Patient
This patient has multiple factors substantially increasing mortality risk:
- Age in late 60s increases mortality risk substantially 1
- Diabetes mellitus type 2 and hypertension confer 3-5 times greater risk of post-infarct mortality 1
- Duration of several hours means ongoing myocardial necrosis with time-dependent salvage window closing 1
- Large anterior MI territory (proximal LAD) carries higher risk of mechanical complications and heart failure 2
Post-PCI Management
Anticoagulation during PCI:
- Use unfractionated heparin or bivalirudin based on bleeding risk assessment 2
- Dose adjustments required for renal function and body weight 2
Admit to critical care unit with continuous monitoring for at least 24 hours, as reinfarction and death occur most frequently within the first 24 hours 2
Monitor closely for:
- Ventricular arrhythmias (have atropine, lidocaine, transcutaneous pacing patches, defibrillator, and epinephrine immediately available) 2
- Mechanical complications (papillary muscle rupture, ventricular septal defect, free wall rupture) 2
- Heart failure development 2
- Recurrent ischemia 2
Echocardiography should be performed to assess for LV mural thrombus given large anterior MI—if present, anticoagulation with heparin followed by warfarin reduces embolic stroke risk 2
Critical Pitfall to Avoid
Do not administer thrombolytic therapy if primary PCI is available—primary PCI is superior for establishing normal coronary flow and has significantly lower risk of fatal and nonfatal bleeding complications compared to fibrinolysis 2. After fibrinolysis, only 50% of patients reperfuse, resulting in high proportions requiring rescue PCI with prolonged ICU hospitalization 2.