What is the prehospital treatment for patients with ST-Elevation Myocardial Infarction (STEMI)?

From the Guidelines

Prehospital treatment for STEMI patients should focus on rapid recognition, initial stabilization, and expedited transport to a PCI-capable facility, with administration of aspirin (162-325 mg chewed) immediately upon suspicion of STEMI, as recommended by the most recent guidelines 1.

Key Recommendations

• Aspirin administration: 162-325 mg chewed, unless contraindicated or already taken by patient, as supported by the ACC/AHA guidelines 1 and the Acute Cardiovascular Care Association (ACCA) of the ESC 1.
• Antiplatelet therapy: Additional therapy such as clopidogrel, ticagrelor, or prasugrel may be considered if available and not contraindicated, with ticagrelor and prasugrel recommended as first-line P2Y12 inhibitors 1.
• Supplemental oxygen: Provided only for patients with oxygen saturation below 90% or respiratory distress, as routine oxygen supplementation is not recommended in the pre-hospital setting 1.
• Pain management: Intravenous morphine or fentanyl can be administered for severe chest pain, with opioid use titrated according to pain evaluation and caution taken to limit doses due to potential interaction with oral antiplatelet therapy 1.
• Prehospital 12-lead ECG acquisition: Crucial for early STEMI diagnosis and should trigger immediate notification to the receiving cardiac center to activate the catheterization laboratory, reducing time to reperfusion therapy 1.

Considerations for Reperfusion Therapy

• PPCI strategy: Recommended if it can be performed in a timely manner, with pre-hospital fibrinolysis considered if transfer delays are prolonged, particularly among early presenters at low bleeding risk 1.
• Fibrinolytic therapy: May be considered if PCI cannot be achieved within 120 minutes of first medical contact and there are no contraindications, with the benefit of fibrinolysis modest beyond 6 hours after coronary occlusion 1.

From the FDA Drug Label

DOSAGE & ADMINISTRATION Myocardial Infarction Early Treatment During the early phase of definite or suspected acute myocardial infarction, initiate treatment with metoprolol tartrate as soon as possible after the patient’s arrival in the hospital. The prehospital treatment for patients with ST-Elevation Myocardial Infarction (STEMI) is not directly addressed in the provided drug labels. However, based on the available information, the following can be considered:

• Aspirin is commonly used in the treatment of STEMI, as seen in the COMMIT study 2.
• Clopidogrel may be used in combination with aspirin for the treatment of STEMI, as shown in the COMMIT study 2.
• Metoprolol can be initiated as soon as possible after the patient's arrival in the hospital for the treatment of myocardial infarction, but the prehospital use is not explicitly mentioned 3. It is essential to note that the prehospital treatment for STEMI typically involves aspirin and may include other medications such as clopidogrel or metoprolol, but the specific prehospital treatment is not directly addressed in the provided drug labels.

From the Research

Prehospital Treatment for STEMI Patients

The prehospital treatment for patients with ST-Elevation Myocardial Infarction (STEMI) involves several key components, including:

• Prompt diagnosis of the acute myocardial infarction
• Patient's risk assessment
• Drug administration to reduce patient's pain and fear
• Prevention or treatment of heart failure 4
• Use of supplemental oxygen, aspirin, nitrates, and opiates 5
• Prehospital 12-lead electrocardiogram (ECG) to diagnose STEMI 5
• Regionalized care for STEMI patients, including primary percutaneous coronary intervention (PCI) 5, 6

Anti-Ischemic Therapy

Anti-ischemic therapy is an essential part of prehospital treatment for STEMI patients, including:

• Nitrates (nitroglycerin) to reduce myocardial oxygen consumption
• Intravenous analgesics (morphine-sulfate) for pain relief
• Beta-adrenergic blockers to reduce heart frequency and myocardial contractility
• Calcium channel blockers to reduce systemic blood pressure
• Angiotensin converting enzyme inhibitors (ACE-I) to reduce myocardial oxygen consumption
• Magnesium and glucose-insulin-potassium to improve myocardial oxygen supply 4

Prehospital Antiplatelet Therapy

Prehospital antiplatelet therapy is also crucial for STEMI patients undergoing primary PCI, including:

• Aspirin to inhibit platelet aggregation
• New parenteral antiplatelet agents that achieve immediate inhibition of platelet aggregation 7
• Potential future management of STEMI involving self-administered antiplatelet agents designed to achieve rapid reperfusion 7

Prehospital Diagnosis and Treatment

Prehospital diagnosis of STEMI is critical to save time and make primary PCI available to the majority of patients, including:

• Prehospital biomarker measurement to gain important additional information 6
• Complementary pharmacotherapy for STEMI undergoing primary PCI, including therapy for pain relief and potential additional strategies for cardioprotection 8