Adenosine as an adjunct to thrombolysis resulted in a 33% relative reduction in infarct size (p=0.03), with a 67% relative reduction observed in patients with anterior infarction.
RCT (n=236)
Open-label
randomized
Does adenosine as an adjunct to thrombolysis reduce infarct size in patients with acute myocardial infarction within 6 h of onset?
Adenosine as an adjunct to thrombolysis significantly reduced infarct size in patients with acute myocardial infarction, particularly those with anterior infarction.
Effect estimate: 33% relative reduction
p-value: p=0.03
OBJECTIVES: The Acute Myocardial Infarction STudy of ADenosine (AMISTAD) trial was designed to test the hypothesis that adenosine as an adjunct to thrombolysis would reduce myocardial infarct size. BACKGROUND: Reperfusion therapy for acute myocardial infarction (MI) has been shown to reduce mortality, but reperfusion itself also may have deleterious effects. METHODS: The AMISTAD trial was a prospective, open-label trial of thrombolysis with randomization to adenosine or placebo in 236 patients within 6 h of infarction onset. The primary end point was infarct size as determined by Tc-99 m sestamibi single-photon emission computed tomography (SPECT) imaging 6+/-1 days after enrollment based on multivariable regression modeling to adjust for covariates. Secondary end points were myocardial salvage index and a composite of in-hospital clinical outcomes (death, reinfarction, shock, congestive heart failure or stroke). RESULTS: In all, 236 patients were enrolled. Final infarct size was assessed in 197 (83%) patients. There was a 33% relative reduction in infarct size (p = 0.03) with adenosine. There was a 67% relative reduction in infarct size in patients with anterior infarction (15% in the adenosine group vs. 45.5% in the placebo group) but no reduction in patients with infarcts located elsewhere (11.5% for both groups). Patients randomized to adenosine tended to reach the composite clinical end point more often than those assigned to placebo (22% vs. 16%; odds ratio, 1.43; 95% confidence interval, 0.71 to 2.89). CONCLUSIONS: Many agents thought to attenuate reperfusion injury have been unsuccessful in clinical investigation. In this study, adenosine resulted in a significant reduction in infarct size. These data support the need for a large clinical outcome trial.
Mahaffey et al. (Mon,) conducted a rct in acute myocardial infarction (n=236). adenosine vs. placebo was evaluated on infarct size as determined by Tc-99 m sestamibi single-photon emission computed tomography (SPECT) imaging 6+/-1 days after enrollment (33% relative reduction, p=0.03). Adenosine as an adjunct to thrombolysis resulted in a 33% relative reduction in infarct size (p=0.03), with a 67% relative reduction observed in patients with anterior infarction.