Gilles Montalescot, MD, PhD; Guillaume Cayla, MD; Jean-Philippe Collet, MD, PhD; Simon Elhadad, MD; Farzin Beygui, MD, PhD; Hervé Le Breton, MD; Rémi Choussat, MD; Florence Leclercq, MD; Johanne Silvain, MD; François Duclos, MD; Mounir Aout, PhD; Jean-Luc Dubois-Randé, MD; Olivier Barthélémy, MD; Grégory Ducrocq, MD; Anne Bellemain-Appaix, MD; Laurent Payot, MD; Philippe-Gabriel Steg, MD; Patrick Henry, MD; Christian Spaulding, MD; Eric Vicaut, MD, PhD; for the ABOARD Investigators; JAMA. 2009;302(9):947-954.
Context International guidelines recommend an early invasive strategy for patients with high-risk acute coronary syndromes without ST-segment elevation, but the optimal timing of intervention is uncertain.
Objective To determine whether immediate intervention on admission can result in a reduction of myocardial infarction compared with a delayed intervention.
Design, Setting, and Patients The Angioplasty to Blunt the Rise of Troponin in Acute Coronary Syndromes Randomized for an Immediate or Delayed Intervention (ABOARD) study, a randomized clinical trial that assigned, from August 2006 through September 2008 at 13 centers in France, 352 patients with acute coronary syndromes without ST-segment elevation and a Thrombolysis in Myocardial Infarction (TIMI) score of 3 or more to receive intervention either immediately or on the next working day (between 8 and 60 hours after enrollment).
Main Outcome Measures The primary end point was the peak troponin value during hospitalization; the key secondary end point was the composite of death, myocardial infarction, or urgent revascularization at 1-month follow-up.
Results Time from randomization to sheath insertion was 70 minutes with immediate intervention vs 21 hours with delayed intervention. The primary end point did not differ between the 2 strategies (median [interquartile range] troponin I value, 2.1 [0.3-7.1] ng/mL vs 1.7 [0.3-7.2] ng/mL in the immediate and delayed intervention groups, respectively; P = .70). The key secondary end point was observed in 13.7% (95% confidence interval, 8.6%-18.8%) of the group assigned to receive immediate intervention and 10.2% (95% confidence interval, 5.7%-14.6%) of the group assigned to receive delayed intervention (P = .31). The other end points, as well as major bleeding, did not differ between the 2 strategies.
Conclusion In patients with acute coronary syndromes without ST-segment elevation, a strategy of immediate intervention compared with a strategy of intervention deferred to the next working day (mean, 21 hours) did not result in a difference in myocardial infarction as defined by peak troponin level.
Free fulltext from JAMA here.