What are the Kenyan guidelines for the acute management of ST‑elevation myocardial infarction?

Kenyan Guidelines for Acute Management of ST-Elevation Myocardial Infarction

While Kenya-specific STEMI guidelines were not identified in the available evidence, the European Society of Cardiology (ESC) 2017 guidelines provide the most comprehensive, evidence-based framework that is widely adopted in resource-variable settings including East Africa 1.

Initial Diagnosis and ECG

• Obtain a 12-lead ECG within 10 minutes of first medical contact (FMC) 1
• Begin continuous ECG monitoring with defibrillator capacity immediately 1
• Do NOT give routine supplemental oxygen unless oxygen saturation is <90% 1

Reperfusion Strategy Selection: The Critical Decision

The choice between primary PCI and fibrinolysis depends entirely on the anticipated time from STEMI diagnosis to PCI-mediated reperfusion:

If PCI can be achieved within 120 minutes of STEMI diagnosis:

• Primary PCI is the preferred reperfusion strategy 1
• Target FMC-to-device time: ≤90 minutes if presenting at a PCI-capable center, ≤120 minutes if transfer required 1, 2

If PCI cannot be achieved within 120 minutes:

• Initiate fibrinolysis immediately (within 10 minutes of STEMI diagnosis), preferably in the pre-hospital setting 1
• This is particularly important for patients presenting within the first 2-3 hours of symptom onset 2

Fibrinolytic Therapy Protocol (When PCI Unavailable)

Use a fibrin-specific agent 1:

• Tenecteplase (preferred for ease of administration)
• Alteplase
• Reteplase

Antiplatelet Co-therapy with Fibrinolysis:

• Aspirin: 150-300 mg chewed or 75-250 mg IV 1
• Clopidogrel: 300 mg loading dose (75 mg if age ≥75 years), then 75 mg daily 1
• Continue dual antiplatelet therapy for 12 months 1

Anticoagulation Co-therapy with Fibrinolysis:

Enoxaparin is preferred over unfractionated heparin 1:

• 30 mg IV bolus followed by 1 mg/kg subcutaneous every 12 hours 1
• Dose adjustment required for age ≥75 years and renal insufficiency
• Alternative: UFH as weight-adjusted IV bolus followed by infusion 1
• Continue anticoagulation until revascularization or for hospital stay up to 8 days 1

Mandatory Post-Fibrinolysis Management:

Transfer ALL patients to a PCI-capable center immediately after fibrinolysis 1. This is non-negotiable.

Assess ST-segment resolution at 60-90 minutes:

• If <50% ST-segment resolution = failed fibrinolysis → immediate rescue PCI 1
• If successful fibrinolysis → routine angiography and PCI of infarct-related artery between 2-24 hours 1
• Emergency angiography indicated for: heart failure/shock, hemodynamic instability, electrical instability, worsening ischemia, or recurrent ischemia 1

Primary PCI Protocol (When Available Within 120 Minutes)

Antithrombotic Therapy:

Before or at time of PCI 1:

• Aspirin: 150-300 mg chewed or 75-250 mg IV 1
• Potent P2Y12 inhibitor (prasugrel 60 mg or ticagrelor 180 mg loading dose) 1
  • If unavailable or contraindicated: clopidogrel 600 mg 1
• Unfractionated heparin (enoxaparin or bivalirudin are alternatives) 1

Technical Aspects:

• Radial artery access preferred over femoral 1
• Drug-eluting stents are standard 1
• Do NOT perform routine thrombus aspiration 1

Post-Reperfusion Medical Therapy

Initiate within first 24 hours 1:

Essential Medications:

• High-intensity statin (atorvastatin 40-80 mg or rosuvastatin 20-40 mg) - start immediately 1
• ACE inhibitor - for all patients with heart failure, LVEF <40%, diabetes, or anterior infarct 1
  • Alternative: ARB (preferably valsartan) if ACE inhibitor intolerant 1
• Beta-blocker - for patients with heart failure and/or LVEF <40% 1
  • Avoid IV beta-blockers in hypotension, acute heart failure, or AV block 1
• Mineralocorticoid receptor antagonist - if LVEF <40% with heart failure or diabetes, already on ACE inhibitor and beta-blocker 1

Dual Antiplatelet Therapy (DAPT):

Continue for 12 months 1:

• Aspirin 75-100 mg daily 1
• Plus prasugrel/ticagrelor (or clopidogrel if unavailable/contraindicated) 1
• Consider PPI if high gastrointestinal bleeding risk 1

Context for Kenya and East Africa

Research from the region reveals significant challenges 3, 4:

• Late presentation to healthcare facilities
• Limited PCI availability (only 79.5% received thrombolysis at Nairobi Hospital, with just 17.9% having rescue PCI) 3
• Inadequate emergency medical services
• Delayed reperfusion times

Given these realities, fibrinolysis becomes the pragmatic reperfusion strategy for most Kenyan STEMI patients, with emphasis on:

1. Early recognition and ECG diagnosis
2. Immediate fibrinolytic administration (within 10 minutes)
3. Establishing transfer protocols to PCI-capable centers
4. Ensuring post-fibrinolysis angiography within 2-24 hours

Critical pitfall: Do not delay fibrinolysis waiting for transfer if PCI cannot be achieved within 120 minutes - every hour of delay costs 1.6 lives per 1000 patients 2.