REOPEN-AMI: Addition of Adenosine to Thrombus Aspiration Enhances PCI Outcomes

MIAMI BEACH, FLA.—Among patients with STEMI treated with PCI and thrombus aspiration, the addition of intracoronary adenosine improves ST-segment resolution and results in a lower rate of major adverse cardiac events (MACE), according to Giampaolo Niccoli, MD, PhD, who presented data from the REOPEN-AMI trial at TCT 2012.

Niccoli, of Catholic University in Rome, and colleagues conducted a randomized, multicenter trial to evaluate whether intracoronary adenosine or nitroprusside after thrombus aspiration was superior to thrombus aspiration alone in patients undergoing primary or rescue PCI.

In all, the trial included 240 STEMI patients who were randomly assigned to thrombus aspiration plus either saline (n=80), adenosine (n=80) or nitroprusside (n=80). The adenosine group was given 120 mcg as a fast bolus followed by 2 mg in 2 minutes; the nitroprusside group was given 60 mcg as fast bolus followed by 100 mcg in 2 minutes; and the placebo group received saline. All patients received a weight-adjusted bolus infusion of abciximab for 12 hours.

Advantage with adenosine

Results showed that the primary endpoint of complete ST-segment resolution was obtained in 71.3% of patients treated with adenosine vs. 51.3% in the placebo group (P=.009). Researchers noted no significant difference, however, between the nitroprusside-treated group and the placebo group for this outcome. Similarly, data suggested a trend toward a lower rate of angiographic microvascular obstruction in patients treated with adenosine vs. those treated with saline, but not between the nitroprusside and placebo groups (see Figure). Clinical outcome data showed that the MACE rate tended to be lower in the adenosine-treated patients vs. those receiving saline (10% vs. 20%; P=.08).

Niccoli noted, however, that the improvement in clinical outcomes and microvascular obstruction seen with adenosine did not reach statistical significance.

In terms of intraprocedural complications, researchers found one borderline difference: transient atrioventricular block not requiring pacing was more common in the adenosine group than in the saline group (12.5% vs. 2.5%; P=.03). No other variables differed according to treatment groups.

Study limitations, Niccoli reported, included the small patient population, which resulted in the trial not being adequately powered to provide information on clinical endpoints, as well as the lack of cardiac magnetic resonance evaluation of microvascular obstruction and infarct size.