The Which Early ST-elevation myocardial infarction Therapy (WEST) trial assessed whether optimal pharmacological therapy at the earliest point of care (ideally pre-hospital) was non-inferior to primary percutaneous coronary intervention (PCI) among ST-elevation myocardial infarction (STEMI) patients.


The WEST trial randomised 304 STEMI patients with symptoms lasting ≥20 min accompanied by ECG evidence of high risk to 1 of 3 groups:

(A) Tenecteplase plus usual care

(B) Tenecteplase followed by routine or rescue PCI within 24 h

(C) Primary PCI with 300 mg loading dose of clopidogrel

The 90-day primary endpoint was a composite of death, re-infarction, refractory ischaemia, congestive heart failure, cardiogenic shock and major ventricular arrhythmia.

Secondary endpoints included 90- and 180-min ST-resolution, and infarct size.

There was no significant difference in the primary endpoint between the three groups (25% versus 24% versus 23%). However, patients in the tenecteplase plus usual care group were more likely to experience a combination of death and re-infarction than patients in the primary PCI group (primary PCI versus tenecteplase plus usual care; unadjusted hazard ratio 0.29; 90% confidence interval [CI] 0.11 to 0.74; p-logrank=0.021). There was no difference between patients in the tenecteplase followed by routine or rescue PCI group and patients in the primary PCI group (p=0.378).

WEST: Outcomes at 30 days

WEST  Outcomes  at  30  days  Primary endpoint shows no significant difference between pharmacologic therapy, pharmacologic therapy coupled with PCI and primary PCI

  • Strategies of thrombolysis coupled to early routine or rescue PCI are non-inferior to primary PCI.


  1. Armstrong, PW. A comparison of pharmacologic therapy with/without timely coronary intervention vs. primary percutaneous intervention early after ST-elevation myocardial infarction: the WEST (Which Early ST-elevation myocardial infarction Therapy) study. Eur Heart J 2006;27:1530-1538