Transcript Trial Overview - Clinical Trial Results

The WEST Trial
Which Early ST-Elevation Myocardial
Infarction Therapy (WEST) Trial
Paul W. Armstrong, WEST Steering Committee
Published in The European Heart Journal
WEST Trial: Background
• The goal of the trial was to evaluate whether early
(pre-hospital if possible) optimal pharmacologic
therapy was non-inferior to primary percutaneous
coronary intervention (PCI) among patients with ST
elevation MI.
• Exclusions include primary PCI available within 1 h of
diagnosis, contraindications to fibrinolysis, prior
coronary bypass grafting (CABG), or glycoprotein
IIb/IIIa inhibitor use within 7 days.
www. Clinical trial results.org
Eur Heart J (2006) Vol. 27, 1530–1538
WEST Trial: Study Design
304 patients with STEMI with symptoms ≥20 minutes and high-risk ECG criteria in whom
reperfusion therapy (primary PCI, fibrinolysis or transfer for rescue PCI) was feasible
within 3 hours of randomization
Randomized.
20% female, median age 58 years, mean follow-up 30 days
Concomitant medications include aspirin and subcutaneous enoxaparin (1 mg/kg)
Tenecteplase (TNK) and
usual care
n=100


TNK and mandatory invasive study
within 24 h and rescue PCI if failed
reperfusion
n=104
Primary PCI with 300
mg loading dose of
clopidogrel
n=100
Primary Endpoints: Death, reinfarction, refractory ischemia, congestive heart
failure, cardiogenic shock or major ventricular arrhythmia by 30 days, evaluated
for non-inferiority of the TNK groups relative to the primary PCI group.
Secondary Endpoint: ST-resolution at 90 and 180 minutes; infarct size
www. Clinical trial results.org
Eur Heart J (2006) Vol. 27, 1530–1538
WEST Trial: Primary Endpoint
• Death or recurrent MI
occurred in 13.0%,
6.7%, and 4.0%,
respectively (p=0.021
for TNK alone vs.
primary PCI; p=0.378
for TNK+invasive
study group vs.
primary PCI).
% patients
Death or Recurrent MI at 30 days
14%
12%
10%
8%
6%
4%
2%
0%
13.0%
6.7%
4.0%
TNK
TNK + Invasive
Study
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Primary PCI
• There were no ICH in
the trial. Major
bleeding occurred in
1.0% of the TNK group,
1.9% of the
TNK+Invasive study
group, and 1.0% of the
primary PCI group.
Eur Heart J (2006) Vol. 27, 1530–1538
WEST Trial: Primary Endpoint
Primary Composite Endpoint at 30 days
25%
25%
24%
23%
TNK
TNK + Invasive
Study
Primary PCI
% patients
20%
15%
10%
5%
0%
www. Clinical trial results.org
• The primary
composite
endpoint at 30
days occurred in
25% of the TNK
group, 24% of the
TNK+invasive
study group, and
23% of the primary
PCI group, meeting
the non-inferiority
criteria.
Eur Heart J (2006) Vol. 27, 1530–1538
WEST Trial: Secondary Endpoint
ST- Resolution at 180 minutes
70%
60%
50%
40%
30%
20%
10%
0%
60.8%
• Complete ST resolution
(≥70%) at 180 minutes
was present in 60.8% of
the TNK group, 69.4% of
the TNK+invasive study
group, and 55.7% of the
primary PCI group.
69.4%
55.7%
• Median peak CK levels
were 1199, 1590, and
1833, respectively
(p=0.045)
TNK
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TNK +
Invasive
Study
Primary PCI
• NT-proBNP levels were
significantly higher in the
primary PCI group
compared to the TNK
group (p=0.019).
Eur Heart J (2006) Vol. 27, 1530–1538
WEST Trial: Summary
• Among patients with ST elevation MI, early reperfusion therapy with TNK,
aspirin and enoxaparin or TNK plus routine invasive strategy was noninferior to primary PCI for the 30 day composite endpoint of death, MI,
refractory ischemia, heart failure, cardiogenic shock or major ventricular
arrhythmia in this pilot study.
• In the present trial, STEMI was diagnosed early and treatment was initiated
early, with 40% of patients receiving pre-hospital randomization.
• The rapid diagnosis and treatment may explain in part some of the
differences between the results of the present trial and other ST elevation MI
trials comparing medical management with primary PCI.
• Unlike the ASSENT-4 PCI trial, TNK with an invasive strategy was not
associated with an in-hospital mortality or stroke hazard, possibly because
the time from TNK administration to PCI was longer in the present trial.
www. Clinical trial results.org
Eur Heart J (2006) Vol. 27, 1530–1538