Yale: Acute Coronary Syndrome: Time to Treatment

CONTENTS

Yale University
School of Medicine
333 Cedar Street
New Haven, CT
06510 USA

(203) 432-1333

Yale

Importance of Time to Treatment in
Non-ST-Segment Elevation Acute
Coronary Syndrome

Time to treatment is important in improving clinical outcomes of patients with acute non-ST-elevation MI.

In the PRISM-PLUS study, there was a 66% risk reduction of death or MI during the first 48 hours in patients treated with tirofiban and heparin compared to heparin monotherapy. Furthermore, the benefit of therapy with tirofiban was seen as early as 12-24 hours after initiation of the fibrinogen receptor blocker. (Fig. 1). This data supports the rapid administration of “platelet-lytic” therapy in the emergency department for patients presenting with non-ST-elevation MI.

Fig. 1. PRISM-Plus: Combined MI and death during initial 48 hours in all patients.

N Engl J. Med 1998; 338: 1488-1497

Similarly, in the PURSUIT trial, there was a clear benefit to early treatment of a GP IIb/IIIa inhibitor. Patients treated with eptifibatide within the first six hours experienced the greatest reduction in the combined endpoint of death or MI at 30 days (14.7% vs. 17.5% with placebo, 2.8% absolute reduction, RR=16%). Patients treated between 6 and 12 hours experienced a 2.3% absolute reduction, whereas those treated between 12 and 24 hours experienced an absolute reduction of 1.7%.

Table 1. Importance of time to treatment with GP IIb/IIIa inhibitor therapy in non-ST-elevation acute coronary syndrome.

Table 1.

N Engl J. Med 1998; 339: 436-443.

In the “early treatment” group (within 24 hours of onset of symptoms), eptifibatide resulted in a significant 2.2% absolute reduction in the composite endpoint of MI and death at 30 days (14.1% with eptifibatide vs. 16.3% with placebo, p=0.003). In the "late treatment" group, the incidence of death or MI at 30 days was similar in the placebo and eptifibatide groups (13% vs. 13.1%, p=NS, Table 2).

Table 2. Importance of time to treatment in non-ST-elevation acute coronary syndrome.

Table 2.

N Engl J. Med 1998; 339: 436-443.

This data confirms the need for early treatment with GP IIb/IIIa inhibitors to improve outcomes in patients with non-ST-elevation acute coronary syndrome.